As you maybe know, Sponge will drop support for API5 and API6 (you can read about it there, especially this:
I am pleased to say that API 7 now has a release date of December 31st, 2017. What this will mean is that API 5 and 6 will no longer be supported, meaning Minecraft 1.10.2 and 1.11.2 will no longer be supported for API additions or bug fixes.
), also, in addition, Pixelmon is now released for API7.
Because of all the above, I will also drop support for API5 and API6 in GWMCrates soon.
Old versions will continue work with old APIs like as they work now, but new versions will be released only for API7, without old APIs support.