documentation for opensource programs varies widely. there is no documentation available for the dB. some hit and miss stuff here and there in the forums. if you want to write it up i'm sure the community would be most greatful
it sounds to me like you need instructions for manually manipulating the dB so you can transfer one dB structure to another.
this is always going to be time consuming and tedious. you can automate things like relocation of data rows. but the tedious part is like adding the image name into the image tag.
i personally prefer to do most of the editing in pipe, the native format. because of the description field sometimes having commas doing it in csv persents challanges. you can also use the pipe as a search feature for replacing stuff or as anchor for other manipulative functions.
make backups of successful transitions so you don't loose too much time and work effort.
the most basic columns you need for proper function are the first 6 columns...
Column 1 - PRODUCT ID # (current number displayed) (change to save as NEW record)
Column 2 - Category - One word only
Column 3 - Price - No $ sign needed
Column 4 - Product Name - 3 or 4 words
Column 5 - Image File - name.gif/.jpg/.png
<IMG SRC="%%URLofImages%%/0006.gif" BORDER=0>
Column 6 - - Description - Enter the Text & HTML describing the product.
this will get your product pages populated so you can customize the layout as necessary. it will also allow you to do test purchases and have most of the fields for the order log and emails. if using options and or userfield data to display on the productpage then you should propbably populate these fields as well befor messing with the ppinc.
if you have tons of products and categories then what i prefer to do is do basic sorting for the entire dB. then do category by category manipulation. sort the dB by category then cut out each category making a new dB for each category. this is advantageous to help reduce the chance of losing all data or coruppting all data as well as keeping relevant references localized. this way you don't have to sort through tons and tons of image names, descriptions and etc.
when done rejoin manually or import by updating not complete overwritting of the dB.
kinda tough not knowing what you're up against but it is going to taske time and work.
dan