Thanks for answering people!
I agree, obviously not everything will work in 360. However, the selection is really much too small I believe. And this small selection is only in PIP, Particle and Title, yet I still have all 147 transitions. Many of the transitions also don't work, so there is a discrepancy here.
The workaround of constantly switching between 16:9 and 360 does work however. When I change aspect, I can drag stuff in and it remains when switching back to 360. A bit clunky to do it this way, but at least I have my options back.
There are indeed a fair few items that DO work in 360 but are not shown as I have found out sofar. So the left out bits are not all incompatible.
I think creative freedom should also be key here. To have your options slashed this severely (leaving only about 10% of my arsenal) doesn't make much sense IMO. It's all non-destructive editing, so if you find something doesn't work, you remove it. And in other cases, something that at first glance doesn't sit well in 360, might make a creative effect in another part of the movie.
PD could show an info box informing me there are compatibility issues with several items and then just show all of them. Or at least give us a much larger section, since there are really more of them that work.
I'm no expert but also definitely not a novice. Around 25 years ago I spent a few years as volunteer at a local TV station, doing edits on broadcast machines (tape to tape editing). Over the years I kept an affinity with video and dabled a bit in free editors and sometimes with (yeah, I know) pirated copies of a few paid ones.
Many years ago I decided to ditch all pirated software, and only did a few little movies in things like Videopad or Moviemaker. Now I want to get a bit more involved and decided to go for it and buy PowerDirector. Very happy with it, though this put me off a little. Good to at least have a workaround by switching to and from 16:9 to 360.
Hopefully there will be more object available in an update.
regards, Frank