PhotoPost Classifieds 4.1 can be used for vBulletin 4.13 forum?
 

I build a forum with vBulletin 4.13. Can I use PhotoPost Classifieds 4.1 on this forum?

Our latest is 4.2 from what I show but either should work with the vb4 series.

several Classifieds in several language
 

I will build several sections of Classified in my vb4.13 forums, each Classified is in one language. So in the meanwhile there will be several Classifieds in several language in my forum. Does it works? If so, How many English words should be translated to other language totally?

A license only permits one install on one domain. You can not install multiple copies unless you own multiple licenses.

You can translate as you wish but most likely you need to create a new language pack for each language. We only release it in english