Hi V,
Pleased that solved your original problem. For the initializing screen This means there is a JS syntax error somewhere.
- open developer tools as described in crib sheet.
- click the red error message that has the name of your file (with the .js extension).
- that will show you the line of code where you are having the error - go back to your BUILDER to fix it or share that error on the discourse page.
For related posts see
https://discourse.psychopy.org/t/stuck-at-initialising-the-experiment/16406/2?u=becca
Hope this helps,
Becca