First off by changing one line of code in last example and tested it with looping 300 times and no problems.
I have to get going but and I have seen other people have problems that are similiar so will type up a better explanation and concepts to show what is happening.
I probably should rephrase the first sentence that I changed one line and no problems. It still a bad approach for the task and there are better ways but understanding why it is not a good approach helps to see what a better one would be.
If you want to start taking a look at what is going on look at methods
with ILSPY or Reflector you see what they do, and notice calls to methods that are explained in docs - acedSSGet, acedSSAdd, acedSSSetFirst, acedSSFree as they all play a role in it.
In the .NET API you actully never will use an instance of a SelectionSet object, one reason would be it is impossible since it is an abstract class.
You actually are using a SelectionSetDelayMarshalled object and there use to be a SelectionSetFullyMarshalled object but was removed in 2010 or 2011 or earlier.
Except for the SelectionSetDelayMarshalled constuctors that take ObjectIds as a argument, the other constructors pass the selection set to a internal class UnmanagedResources method AddSelectionSet which adds it to a key value pair collection, which passes it into constructor of a DisposableSelectionSet object.
I know that is a little jumbled but will make a better explanation later tonight or tommorrow .
Anyway the only change made was commented out first line and added second.
I greatly appreciate your time with your response. You have indeed fixed my issue with that little change. I am not sure I understand much in your message or why this one little change makes the difference but it does. Perhaps I can figure out why someday.
Okay, That makes a bit of sense to me. Never would have thought about that when troubleshooting my code. I looked at that line numerous times while troubleshooting but just wasnt sure what else to use.
Thanks so much for your help! Greatly appreciated!