Whew! This one was a little tricky to reproduce since in theory, any given lag spike that was formerly caused by shader variant compilation for this game would happen only once each on your device, ever. This is because after a shader variant is loaded for the first time, you'll have a nifty little cached file saved in your OS for next time. So to reproduce this issue, I just needed to delete these cached files in order to observe the behavior, and voila, the awful lag spike shows its ugly face on my computer. Sorry everyone who had already experienced this! The fix is in.
Without preloading - Very first time compiling shader variant (BEFORE):
With preloading - No more hitch (AFTER):
Oof. This is one of a few specific levels that the lag spike would consistently occur on, for all players.
Some feedback has been that it's too easy to start fidgeting around without even realizing where the current outflow is in some levels. I've now marked the outflow/potential victory positions with bright flowing water, to help the player's eye more quickly identify this important element of the puzzle. If it's not enough, even more may be added in the future, like particles and glowing effects!
There are other performance issues and optimizations that are actively being investigated. Expect more improvements for the full release, and please do feel free to share any concerns or findings here in the community hub. Thanks for reading, and have fun puzzling!