Applescript dictionaries disappearing

I am new to Applescript, and I'm writing some very simple scripts for MS Word automation, then triggering them via Keyboard Maestro and a stream deck.

Since updating to Sequoia my applescript dictionaries keep disappearing... making it rather tricky to prepare new scripts. It's seems that if I use a dictionary a few times, it stops opening. If I open other dictionaries a few times, these then disappear and the previous can be reopened once or twice before disappearing again. It seems to apply to all apps.

Apple support say they won't help, although the machine is covered by Apple Care... The events have been observed and recorded by Apple support who confirmed my description. A week later I was told they aren't allow to send applescript questions to the engineers and they aren't allowed to help further on this.

Does anyone have a suggestion on what might be going wrong, and how I can stop my dictionaries from disappearing?