Keygen means a small program that will generate a cd key, serial number, activation number, license code or registration number for a piece of software. All retail software uses a serial number of some type, and the installation requires the user to enter a valid serial number to continue. Serial means a unique number or code which identifies the license of the software as being valid. A crack is a program, set of instructions or patch used to remove copy protection from a piece of software or to unlock features from a demo or time-limited trial. Crack means the action of removing the copy protection from commercial software. If you are still having trouble finding Res2dinv Ver.
If this is the case then it's usually included in the full crack download archive itself.