Lubuntu Disable [alt] + drag move window

Question

I've tried everything Google has to offer. Using a computer as a dedicated Blender machine and just need a lightweight desktop. Installed mini.iso (32-bit 14.04) and selected the "Lubuntu Minimal Installation" at install. Exactly what I needed - hardly uses any resources to run Blender. The Alt key, however, remains positively obstinate in its insistence to a) move the window when held with drag and b) not allow a Blender key binding in Blender's input settings. When modifying bindings in Blender, I can hold Ctrl+Alt, click LMB and it binds just fine. If I hold Alt and click LMB, it refuses to recognize the Alt modifier. However, when I let up on the Alt key, it's perfectly happy to bind the action to plain Alt. My attempts at a resolution are listed below.

Removed all traces of "A-Up/Down" bindings in rc XML files in both ~/.config/openbox/ and /etc/xdg/openbox (typing the paths from memory - hopefully these are correct). After failed attempts here, I even deleted everything but the top-most XML tags and still no success.

Installed dconf-editor and removed the mouse modifier in org > gnome > desktop > wm > preferences > mouse-button-modifier. I understand with this one that clearing it can enable all buttons as modifiers so I set this to <Shift> just to test.

Installed CCSM and verified that the Move Window plugin was disabled. Also, explicitly set modifier key to Disabled.

Ubuntu 14.04 32-bit Lubuntu Desktop

Update:

I've got part of it solved. Commented out the <mousebind button="A-Left" action="Drag"> tag in the <context name="Frame"> tag (was looking in the context name="Desktop" tag before). This disables alt-drag in the window but I'm still unable to bint Alt+Left Click in Blender. I've tried a) exporting the key settings, manually setting "Alt", then importing and b) searching for possible conflicts with other Alt+LMB bindings and removing. Still no success.

Answer 1

Finally got it solved. I was looking in the Desktop settings of the rc config when the settings I needed were in the "Frame" tag(<context name="Frame">). Commenting out all three <mousebind button="A-Left" action="Press/Click/Drag"> tags stopped the window from moving and allowed Alt+Left Mouse to be bound in Blender as usual.

I should also mention that I only edited the file ~/.config/openbox/lubuntu-rc.xml and didn't modify anything in /etc/xdg/openbox/rc.xml. After the modifications, I ran openbox --reconfigure in the terminal and restarted just to be safe. This was done after a clean install and no additional settings were modified, also no additional settings managers were used.

Answer 2

You can also open Window Manager Tweaks (found through the Application Finderwith ALT + F3), choose ACcessibility and set Key used to grab and move windows to None.