You can run v5.35 alongside v6.xx without driver conflicts or path errors.
By default, MPLAB X stores settings in your Windows User profile. To make it truly portable, you need to redirect these folders. download mplab x ide v535 portable
Carry your entire development environment on a thumb drive. You can run v5
An IDE is useless without compilers. To keep the setup portable, download the XC8, XC16, or XC32 compilers and extract them into a subfolder within your portable MPLAB directory. When you launch the IDE, manually point the "Build Tools" options to these local folders rather than the system default paths. System Requirements and Compatibility Windows 7, 8, or 10 (64-bit recommended). download the XC8