Got frustrated after losing hours of work yet again to this found what is hopefully helpful info for this.
What's happening it seems is the dialog is is being loaded behind CMO main window and getting modality or focus and not being brought to the forefront, or alternatively modality is lost on the main window but the new one isn't being drawn\spawned yet till the minimize-workaround mentioned next happens. The only way (and I can consistently do this as a workaround now that I found it) is to via task manager (or winkey+downarrow) highlight the CMO app and specifically trigger a 'minimize' from there, then the dialog window instantly loads\shows up center screen (and on taskbar but only after you select it) where you can make your edits or cancel.
I don't know what it's doing\checking before showing the dialog but whatever it is seems to have different results depending on save\scenario beyond the contents of the text. This also happens with: Game\Side briefing, Game\Scenario Description, and Editor\ Edit side briefing - HOWEVER in those cases the game itself doesn't lockup-lose modality so you can minimize normally and then the window will show up onscreen\on taskbar.
I can reproduce this in CMO 139.2 and 141.2 100% of the time on my system with the attached scenes on my system, one sample is a save of the relative end state of playing a modded fiery cross reef, and two others are just some random things I was playing around with and those two only include a couple dozen units. Both show the behavior 100% of the time for me after being loaded, where most older community and included scenes I tested don't show the behavior, nor does a brand new scenario with like 2 sides and a couple generic modded units.
BTW I've also seen something similar happen with the shift-f1 manual fire screen after using it a hundred+ times after like 12+ real hours into playing a session where the screen is gone and you should be selecting a unit\target but you can't select any unit or shift-f1 to bring it up again. It's probably a separate issue I just mention it because funny enough the solution when that bug happens with shift-f1 is usually to trigger the scenario description edit dialog, which for whatever reason seems to reset the cursor or cancel out of the manual fire process that gets fubar'd.
@BeirutDude - Try the forced minimize work around, let me know if it works for you and it's not just some freak fix applying only to me.
< Message edited by KnightHawk75 -- 4/12/2020 10:02:32 PM >