Hi Alex,
About "WebAssetManager is Locked...."
Forum Joomla: https://forum.joomla.org/viewtopic.php?t=994191
and also found: https://regularlabs.com/forum/modulesanywhere/49465-webassetmanager-is-locked,-you-came-late
I don't see relation with our extensions nor template for that.
About sentence "nothing works with the Helix3 template" - you forgot about VERY IMPORTANT THING. You don't have Template from JoomShaper, it only uses our engine.
Your Template is named FLEX ! It means that support should be delivered by Aplikko
Read JoomShaper Support Policy 8.8
You are not the first and probably last webmaster who has problem with Flex template.
We could help ONLY if you would have raw Helix3 template or template bought here. Otherwise, there is a extra fee ($) for assistance.