Drag and Drop - More than 1 per project? - Captivate 9

Does anyone know if there is an issue with having more than one Drag and Drop Interaction (D&D) in a single project? I had a fairly stable project with one D&D, and when I built a second the project started behaving very erratically. One copy of the project crashed and corrupted the file so it wouldn't open. Another copy would allow the second D&D to preview fine but wouldn't work in Edge Inspect or when published to HTML5, then promptly crashed Captivate, and corrupted the installation so I had to re-install the program. Then finally... another copy of the file allowed the second D&D to work when published, but only in Explorer - and with many other errors in playback.

If I know that it's a rule that more than one D&D per project isn't allowable then I will plan the projects accordingly - or is it just a one off instance.

Any ideas anyone as I'm up against many deadlines and only have so much hair left to pull out.

Many thanks,

Ashley