When assigning hotkeys in themes, what do you find to be the
best way to avoid collisions with user defined hotkeys? To
follow the OTS we cannot load hotkey modules, but can define
hotkeys. But, there is no "block" of reserved definitions,
(at least as I understand it) in the standard.

The OTS disallows modifying anything in the profiles\personal
folder, correct? Do you just ";" comment out any hotkey
assignments and other personal settings, allowing the user
to uncomment them for use? Or, is the OTS sometimes ignored?

You can't really reserve definitions for hotkeys since anyone can define their own. Your best bet is to avoid defining hotkeys in your theme that are defined by default in a fresh ls installation.

If you are creating hotkeys in your theme you should define them in the themevars.rc file and document them in your readme. A disciplined LS user will know to look in these two files for information about configuring a theme.

"The OTS disallows modifying anything in the profiles/personal folder, correct?"

Incorrect. You can modify these files as you, the user, pleases, provided you only change the settings. As a theme creator you only need to realise what variables exist inside these files and do not create a conflicting setting in your theme. The theme creator does not distribute the personal.rc file in his/her theme so it makes no difference what changes he/she makes to his/her own personal.rc file. The idea is to not create a conflict.

Thank you DrWorm. That clears up the hotkey issue for
for me. One thing I am still not sure about. In
reference to the personal settings of a user, looking
at them as a themer. When a theme contains its own
rainlendar .ini or skin, this over-rides the users'
personal settings. Is this ok also, as long as the
user is warned in the readme?

I would say no. I haven't used rainlendar before but I question the need to override the users preferences. You should still be able to define your own skin for rainlendar. But I don't know enough about rainlendar to give a definite answer or advise.