I added a little kludge to my HalfShell utility for FreeCommander 2009.02b
HalfShell opens folders selected in Explorer either using SysWow64\explorer.exe on a 64 bit system, explorer.exe in 32 bit system, or you can use an alternative file manager(shell) and it will open folders using that program.
If FreeCommander is the "Alternative Shell" in use when HalfShell is in Alternative Shell mode, it used to just launch FreeCommander.exe with 1 or 2 folders listed on the command line. Now if more than 2 folders are selected it will use a macro to open them in new tabs.
To show what I mean, here's an Explorer window with 7 folders selected:
At this point if you hit Shift-Enter FreeCommander ends up like this:
(Note the right hand side has 6 folder tabs.)
If FreeCommander is already running then all the folders are added as new tabs on the side that has the focus when the window is activated. This is, of course, provided you didn't change the key bindings. Control-t to open a new tab and Alt-g to open the edit line for the tab.
Just a kludge but fun.