Hi Dreamora,
Oh dear, once again I am reminded of why I should never upload updates after midnight. With this one I have included an incorrect path name in the extensions file. The correct extensions file can be downloaded
from here. This file should be saved over the 'extensions.ini.xml' file in the following directory:
C:\Documents and settings\[your name]\Application data\Bundysoft\L3DT\Pro 2.5.0.24\Settings
The reason the drag-n-drop didn't work is because the plugin is still technically installed, even though it's not where L3DT thinks it should be. To re-install the plugins you would need to go to the extensions manager an unload then all first.
I apologise for the inconvenience caused by this cockup. I'll update the installers later today (for now they're "temporarily unavailable").
Best regards,
Aaron.
PS: The changes in RC4 are just revisions of the BT and HF2/HFZ plugins to better support georeferencing.
Update: The 'fixed' installers have been uploaded.