那士隐夫妇,见女儿一夜不归,便知有些不妥,再使几人去寻 找,回来皆云连音响皆无.夫妻二人,半世只生此女,一旦失落,岂不思想,因此昼夜啼 哭, 几乎不曾寻死.看看的一月,士隐先就得了一病,当时封氏孺人也因思女构疾,日 日请医疗治.

My try:
When 士隐 and his wife saw that the daughter did not return home after one night, they knew there were was a problem. Again several people were sent to search –  only to come back reporting that not even the slightest information could be gathered. The couple who had only that one daughter born in an eternity, fully understandable mourned day and night, almost wanting to die. In that a  month first 士隐first fell ill, then, thinking of that girl 封氏孺 also got sick. Day after day visited the doctor for remedy.

Breakdown:
那士隐夫妇,见女儿一夜不归
When 士隐 and his wife saw that the daughter did not return home after one night

便知有些不妥,
Therefore knew there were „a few not appropriate“ -> therefore knew that there was a problem

再使几人去寻 找
Again then send(let) a few people go to search

回来皆云连音响皆无.
Returned all said not even a (音响) sound was not heard
连…皆  - equivalent to 连。。。都?

夫妻二人,
The couple

半世只生此女
Half a century only born that woman ->
[that] for an eternity only had that daughter born

一旦失落,
in case of loss

岂不思想
Won’t it mean the thought
-> I understood that as: it obvious/clear that

因此昼夜啼 哭
therefore day and night (啼 哭) mourned

几乎不曾寻死.

Almost (不曾) never search for death -> amost wanting to die

看看的一月
In that month (lit: "Look at one month")

士隐先就得了一病
士隐first got sick

当时封氏孺人也因思女构疾,
That time 封氏孺 also because of the thought of that girl got sick

日 日请医疗治.
Day after day visited the doctor for (疗治) remedy

不想这日三月十五,葫芦庙中炸供,那些和尚不加小心,致使油锅火逸,便烧着窗 纸. 此方人家多用竹篱木壁者,大抵也因劫数,于是接二连三,牵五挂四,将一条街烧 得如火焰山一般. 彼时虽有军民来救,那火已成了势,如何救得下?直烧了一夜,方渐 渐的熄去,也不知烧了几家.

My try:
Unexpectedly at the day of March, the 15th, in the monastery 葫芦 there was food frying for scarifying to the gods. Those monks were not careful enough to prevent the fryer from bursting into flames, then the window curtains caught fire. In this place everybody extensively used bamboo fences and the wooden walls for building houses, probably it was predetermined fate. As a result step by step the street turned burning like a sort of “Mountain of Flames”. Although firemen came for rescue, at that time the fire already had become powerful, how could it be stopped? It had already been burning a whole night, when it was slowly extinguished and it was unclear how many homes were burned down.

Breakdown:
不想这日三月十五
(不想) unexpectedly at the day of March the fifteenth

葫芦庙中炸供,
in the monastery 葫芦(炸供) there was food frying for scarifying to the gods

那些和尚不加小心,
those monks (不加小心) were not careful enough

致使油锅火逸
to prevent the fryer from bursting into flames

便烧着窗 纸   
then the (窗 纸, lit. „Window paper“) window curtains caught fire
 
此方人家多用竹篱木壁者
In this place everybody (多用) extensively used (竹篱) bamboo fences and the wooden walls (木壁者) [for building houses]

大抵也因劫数
(大抵) probably (劫数) it was predetermined fate

于是接二连三, 牵五挂四
As a result (接二连三) one after another, 牵五挂四 (one after another) -> step by step

将一条街烧 得如火焰山一般
the street turned burning like a (一般) sort of (火焰山) Mountain of Flames (also insurmountable obstacle)

彼时虽有军民来救,
(彼时) That time although (军民) firemen [lit: soldiers and civilians] came for rescue

那火已成了势,
That fire already had become (势) powerful

如何救得下?
How to save (=stop the fire)?

直烧了一夜
[Already] Burning a whole night

方渐 渐的熄去
(方) Just/then it was slowly extinguished

也不知烧了几家.
And it (不知) was unclear how many homes were burned down

只可怜甄家在隔壁,早已烧成一片瓦砾场了.只有他夫妇 并几个家人的性命不曾伤了. 急得士隐惟跌足长叹而已.只得与妻子商议,且到田庄 上去安身. 偏值近年水旱不收,鼠盗蜂起,无非抢田夺地,鼠窃狗偷,民不安生,因此官 兵剿捕,难以安身.士隐只得将田庄都折变了,便携了妻子与两个丫鬟投他岳丈家去.

My try:
Only that home of pitiful 甄 next door earily burned down to a pile of rubble and just the the lives of a couple and a few servants were spared. All the troubled 士隐 could do was stamping on his feet and sighing deeply. He discussed with his wife [about] further proceeding to a place in the countryside to live there. Unfortunately just this year water logging and drought led to a poor harvest, robbers came and nothing was left after they robbed the fields – “they played petty tricks on the sly like rats that filch and dogs that snatch”. People could not live a peaceful life and therefore the police came and started hunting down this bandits. It was really difficult to live in peace and so 士隐 had to sell off all of the land and take his wife and two servant girls and went with them to get help to the home of his parents in law.

Breakdown:
只可怜甄家在隔壁
Only that home of pitiful 甄 next door

早已烧成一片瓦砾场了
early burned down to a slice/pile of (瓦砾场) rubble

只有他夫妇 并几个家人的性命不曾伤了
only the lives of a couple and a few servants (不曾伤了) was spared

急得士隐惟跌足长叹而已.
Troubled 士隐 (惟) (could) only (跌足) stamp on his feet and (长叹) sigh deeply.

只得与妻子商议,
Only discussed with his wife

且到田庄 上去安身
[about] further proceeding to a [田庄] place in the countryside to [安身] live there

偏值近年水旱不收,
(偏) unfortunately directly this year (水旱) water logging and drought (不收) led to a poor harvest
   
鼠盗蜂起,
rats robbed and (蜂起) insects rose
-> Considering the following text I interpret this as “robbers came”

无非抢田夺地,
(无非) nothing was left after (抢田夺地) [they] robbed the fields

鼠窃狗偷,
fixed expression: „played petty tricks on the sly like rats that filch and dogs that snatch”

民不安生,
people could not live a peaceful life

因此官兵剿捕,
therefore the (官兵) police/government troops went and (剿捕) hunted down those bandits

难以安身
it was (really) difficult to live in peace

士隐只得将田庄都折变了,
士隐 (只得) only could (折变) sell off all of the land

便携了妻子与两个丫鬟投他岳丈家去.
and take his wife and two (丫鬟) servant girls and (投) went with them to get help to the (岳丈家) home of his parents in law

他岳丈名唤封肃,本贯大如州人氏,虽是务农,家中都还殷实.今见女婿这等狼狈 而来, 心中便有些不乐.幸而士隐还有折变田地的银子未曾用完,拿出来托他随分就 价薄置些须房地,为后日衣食之计.那封肃便半哄半赚,些须与他些薄田朽屋.

I have some trouble with three parts in this section that I marked red in the breakdown.

My try:
His father in law was called 封肃, a native from a place called大如州. Although being in the agriculture business, the family nevertheless was well-off. Now that he saw the son in law hat come in such a difficult situation, he therefore felt very unhappy. Fortunately the money 士隐 got from selling off his land had not yet been used up. He took it and entrusted it to him to get a share which was - under consideration of the market price - a rather small field and house. Preparing for the living later that 封肃 therefore was half cheating, half making money. He gave him a little meager field and a rotten house.

Breakdown:
他岳丈名唤封肃,
His father in law was called 封肃

本贯大如州人氏
That (贯) native place 大如州 [was his] (人氏) place of origin -> He was a native from a place of 大如州

虽是务农,
Although (务农) being in the agriculture business

家中都还殷实.
the family nevertheless was (殷实) well-off

今见女婿这等狼狈 而来,
Now that he saw the son in law hat come in such a (狼狈) difficult situation

心中便有些不乐.
He therefore felt (有些 - “a bit”, I guess this is understatement) very unhappy (in his heart)

幸而士隐还有折变田地的银子未曾用完,
Fortunately the money 士隐 got from selling off his land (未曾) was not yet used up.

拿出来托他随分就 价薄置房地,
He took it (托他) and entrusted it to him (随分) to get a share (就价, “by the price”) – [which was] under consideration of the market price - (薄置) a meager field and house

为后日衣食之计
Preparing for the living later

那封肃便半哄半赚,
That 封肃 therefore was half cheating, half making money

些须与他些薄田朽屋
(与他) Gave him (些须) a little (薄田) meager field and a (朽屋) rotten house