Using OLD Builder.
Random loss of edited/added script on JS mappings of rest service.
AND
Appery builder not loading resources like images and CSS.
AND
Images assets go missing in builder. (ie while project open. open a screen tab that has images on it. There not there. Look at Media Manager, shows image names but no pics)
Edits of a main JS page are NOT saved.
YES I cleared browser cache, YES I tried firefox instead of Chrome.
Some of These problems started after your last update. Others since 2 days ago.