Downloaded files aren't working

[Sorengaard]

Hey all,  Being new I have recently downloaded a number of different files.  Some of them I can access while playing the game while others I can't.  I know there are some files that can only be accessed later in the game but I am sure many of these aren't those kind.  So I am at a loss as to why.  Is there a checklist of some kind that I could use to try and determine what is wrong because I am not sure where to even begin to look for the whys? 

Also is there a glossary of some kind that would define terms as well as the acronyms that are so often used?

Thanks one and all

[Pat]

Hiii Sorengaard welcome to Devo and Well for terms and there defintions you can click here [linkie] that will help for one part...  can you please provide some examples of what is not working or showing up in game that you recently got...  It can be a chance what you have downloaded needs to grow when the demand is met to make it grow...

[Sorengaard]

Hi   Thanks for the glossary.  It's just what I was looking for.  While I am sorting through files as to examples of problems could you explain what the different files mean?  Lot ... Model ... Desc ... DAT and do the effect how things work in the game? Is there a reason the Prop files are DAT? Thanks again for the glossary.

[xxdita]

Time for a crash course in SC4 101.
*.sc4model - this is the actual 3d building model required for the lot to show correctly. Can also be in *.dat format to compress the file a bit.
*.sc4desc - this is the file that tells the game exactly how that model should fit, and the properties it should have. Often, this is tidied up into the actual *.sc4lot file, to make things simpler.
*.sc4lot - this file tells the game which model to show, on how big of a lot, with which props where, and other assorted information. Ideally, the desc exemplar is included in the lot file, to help the end users keep their plugins folder more organized.
*.dat - often a combination of any of the above files. If the file is a Mega Prop Pack, then most probably, it only contains model files and maybe the desc files for props.
Welcome to SC4D and playing the game with Custom Content!