This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
Using the FEditorModeID for the different editor modes does not affect actual modes available in editor Modes tab.
Example:
Command "Mode EM_Foliage" does not switch to the foliage mode
Workaround:
Using hardcoded mode instead does work (ex: Mode Foliage)
Result:
Modes tab does not switch to Foliage
Expected:
Using FEditorModeID allows tab to switch modes based on FEditorModeID used
Head over to the existing Questions & Answers thread and let us know what's up.