Here is a short guide on how to successfully compile and use these types of file packs. 1. Understanding Multi-Part Archives
To "develop" the pack into a usable format, follow these steps:
Right-click only on Part 1 . Your extraction software (like WinRAR or 7-Zip) is programmed to automatically find Part 2 and the rest of the sequence once you initiate the process on the first file.
Once the pack is compiled, "developing" it further means checking the contents for a README.txt or Install.nfo file. These files usually contain the specific instructions provided by the creator on how to use the assets or install the software contained within.