As you noted, the response ID used in AppSheet is the public response ID from Forms as exposed in Forms URLs and the Forms API. It appears that Apps Script came up with their own encoding of the same ID which is not compatible. AppSheet has no access...

Thanks for reporting this. We have tracked down an issue where Forms events subscriptions were failing to renew and this was causing events to no longer be sent to AppSheet. This issue was resolved yesterday (July 30) and automation should be firing ...

If we were to add support for reading multiple uploaded files from the form response, would the preference be for Drive URLs as they are exported to Sheets, or for a format with a list of file IDs like @Koichi_Tsuji referenced above? DocId=xxxx , Doc...

You are correct about the 1 file limitation. The existing AppSheet file column types only support a single file. This is documented in Create an app using Google Forms. This note could be added elsewhere in the documentation if there is a place you w...

This integration does not require the use of the AppSheet Events add-on. Events are delivered directly from Google Forms. There doesn't even need to be a Google Sheet linked to the Form.