Bonorose,
LogPlayLevel: CommandEnvironment.SetupBuildEnvironment: WARNING: ERROR: NOTE: Please ensure that 64bit Tools are installed with DevStudio - there is usually an option to install these during install
LogPlayLevel: CommandEnvironment.SetupBuildEnvironment: WARNING: Assuming no compilation capability.
This sounds like an issue we saw quite a few version ago. Please check out this [AnswerHub post][1] and see whether or not the suggestion fixes the issue.
If that does not work, install 4.12.5 or 4.13 and see if you’re still having HTML5 complications.
Thank you!