I'm trying to program the latest versions of the bootloader (both, USB or Serial) throught the Chipkit Programmer and MPLAB IPE v2.26. However, when I try load the hex files the software only say "Loading hex file. Please wait..." and don't continue. The source of hex files is "https://github.com/chipKIT32/PIC32-avrdude-bootloader/tree/master/BootloadersCurrent-hex ". I understand that these are the latest versions.
These are the latest community supported bootloaders. Consider that you need to select the correct uC that is one your board when you use IPE, failure to do so may result in a loading that works but a bootloader that does not. If you have a bootloader that you think is not working please log an issue on the github account for the chipKIT32 team. It easier to track and will have greater visibility for the team.