Descriptive Problem Summary:

Numbered Steps to Reproduce Problem:
1. Select a new object type to place by clicking the an entry in object type tree
2. Click any particular variant in the pane to the right of the type tree. Beep sounds.
3. Place a few of this variant of an object, noting that it should work normally.
4. Select a different variant from the right pane. beep sounds
5. Go to place this variant

Expected Results:
Newly selected variant is placed

Actual Results:
Originally-selected variant remains the one being placed, despite the second one showing as selected

Does the problem occur:
Every time? Or how often? Sporadically, more often after longer periods of map development work
In other games? N/A
In other user accounts? Not Checked
On other computers? Yes

When does the problem NOT occur?
When alt-selecting an object already in the map or picking a new object from the type tree

Did the problem NOT occur in any earlier versions? If so, what was the last version that worked?:
The problem has been around for a while

Workarounds:
Keep trying until it finally places the correct object

Now, I probably have the name wrong, but by the variant selector I mean the panel directly to the right of the object type tree / file tree panel.