Back to your original question.
Without much research on past versions.
I believe that around version 7.5.6 it was determined that, members were having issues with their host upgrading the php,apache and mysql versions. So it was up-graded to support the newer versions.
Even though the current version should be backwards compatible somewhat.
So I would suggest you try prior to 7.5.6.
Giz is just trying to figure out what the issue is because it should work.