Build went ok but Install didn’t. Installing restarted Monterey. Tried a few times. After fresh reboot and also after doing a deep clean and doing a new build.
The iscreensaver that was installed at time of updating to beta 6 works ok. I rebuilt that one on Beta 6 and it installed ok but it is smaller than my new one.
Anyone else on Beta 6? Working ok? I’ll do some back-tracking tomorrow in case I screwed something up as I’m still adding images 
After some back-tracking I found that my latest project is the culprit. This project is now 4.1GB in size. The install dialog sits/hangs at 2GB when system reboots.
Confirmed that the problem is one or more images of mine. Been adding in batches of 25 and had the iMac reboot on 2 different batches.
A bit more info…
Project that was built and installed on Monterey b6 had some images where “Landscape” was not applied, even though it showed set to Landscape for the media. Images showed short and wide.
Reset the images by selecting Crop and then back to Landscape and images showed correctly in Preview. Project built ok but did not install.
Copied the install zip to MacBookPro on BigSur and it installed ok.
Tried the install zip on Monterey b6. It reset the iMacPro same as if install was called from within iScreensaver app.
In the process of copying my 300+GB PhotoLib to the MacBook with BigSur and will do a build/install there to see what happens.
Update: Builds and installs ok on BigSur.
Update2: Booted BigSur on iMacPro and the Monterey built screensaver installed ok. Considering a downgrade and scrap Monterey for now. If nothing else, by the time I get downgrading done Monterey will be fixed - That’s how it usually works for me.
Been busy downgrading to Big Sur.
The BIG unexpected, even though I should know better… Photos Library no good as it’s been upgraded by Monterey Photos app. That was a biggy, still is. Currently rebuilding a Big Sur Photos Lib from iCloud. That’ll take a few days I suspect, to get all the originals downloaded.
In the meantime I saw that there was a new iScreensaver so I thought what the heck, lets give it a try on Monterey. Lo and behold, project built AND installed, just as I know it would as per my previous post
Going to try and stick with Monterey Beta, at least while Big Sur Photos is rebuilding. Fingers and toes crossed I’ll be able to stay there. Definitely a very hard lesson learned re Betas. But that last few where sooo good
An aside… don’t expect macOS to migrate from TimeMachine that is on a NAS. I had to do a TimeMachine backup to a local drive before it would migrate successfully during my rebuild.
Afterthought… could have been a fluke that install worked but I’ll take it. I’ll do some more work on my ‘project’ in Monterey once nerves have settled a bit
By now I’ve done a few edits, builds and installs with latest iScreensaver. All good.
Images that on a prior version didn’t ‘see’ the Landscape setting and displayed short and fat are all good without having do anything extra.
Time to add more images
Still hanging with Monterey Beta.
My project is complete with reference to images added, until more paper pics are digitized anyways.
7.9 GB, 7275 images covering from early sixties to almost today. Still lots of tweaking to do as some images look better with Crop setting versus Landscape. Had lots of 480x640 images from early cameras, set this to actual size.
Having FUN building and viewing !!!
Super glad to hear you are enjoying this - the fact that iScreensaver can import directly from Photos.app and automatically handles LivePhotos is one of the strongest features (in our humble opinion).
We also really apprecaite your help with bug testing feedback and beta testing - customers like you are awesome!