Easy2Boot mainly consists of grub4dos, grub4dos utilities and grub4dos scripts and these can be freely used by anyone.
If you wish to use my grub4dos scripts commercially however (i.e. sell it as part of a product), a donation would be much appreciated, especially if you would like any help or modifications! Technicians within a company (even if a one-man+dog company) are free to use it - just please don't sell it!
However, the E2B download contains a few small programs which may not be free to use commercially and it is up to you to obtain permission for all .exe programs within the E2B download that you may use. The author of WinContig.exe states it is free for commercial use. The Easy2Boot download also contains RMPartUSB (used to format a USB drive only) which cannot be used for commercial purposes or re-distributed (see below) - however it is only used to partition a USB drive and so is not used after that and other utilties can be used to format a USB drive and install grub4dos (e.g. BootIce or FBInst).
The MPI Tool Kit does contain some 3rd-party utilities which AFAIK are free to use and distribute (but not open source).
Please do not re-distribute the E2B download packages or the MPI Tool Kit. Instead just link to this site.
Some of the E2B Windows utilities and scripts that I have written (e.g. SWITCH_E2B, E2B_Editor, TXT_Maker) can be freely used or distributed. XMLtoE2B requires a licence file which contains the user's name and email address and so the licence file should not be distributed.
RMPrepUSB and RMPartUSB
RMPrepUSB and RMPartUSB are not open-source.
These two programs are free for public use, but should not be used in a commercial product or redistributed or made available for download, either as a standalone download or as part of a package, without permission.
Note that the MPI Tool Kit contains RMPartUSB.exe and so will any .imgPTN images made using it (though you can delete it).