The Community Database Cleanup Project (CDCP) is a mod which sole purpose is to fix all the mistakes, typoes, errors and other such "small" issues in HOI2-DDA which are solvable by modding files. This is the closest thing the HOI2 community has to an "unofficial" patch. This mod has since incorporated into the 1.3 patch so there is no need to download it.
CDCP is a specialized mod intended to simply fix minor game errors. As such, the mod should be fully compatible with all other mods as long as you install CDCP before anything else. Installing CDCP before installing major mods like TRP or CORE, will however be waste of time. These mods changes more or less everything, in doing so they remove all changes made by CDCP.