Version history
From 3DGE Wiki
Test Version
Test versions are builds usually designated with the prefix RC, for Release Candidate, TESTx, for TEST (x = number), or by Version Numberx (where x = version number).
There are usually a TON of these before 3DGE hits a stable (and final) release. Early TEST versions are usually incompatible with STABLE releases, including savegames. Some are from different codebases altogether.
Stable Version
Stable releases are usually the last in lineage (for instance, 1.36A-F, with F being "Final" and thus reaching "Stable"). These are the ones that are guaranteed to work as intended.