If I click Select a resource (pic below) then click Create a resource
I'm greeted with an error page on the pop-up:
I don't know if it will be helpful but I've attached the console log file (I can't upload .txt, so it's saved as .json.... just rename it to 'retool-log.txt' or use 'Open With...' and select notepad)
retool-log.json (33.4 KB)
just some notes:
when clicking the Select a resource dropdown, the first set of errors appear:
then when I click on Create a resource the other LONG errors dump to the console:
I've alerted the team and will let you know here as soon as I have an update. 
Happy building!