I don't have pdaXii13, so I don't personally have Meanie's keymap, but I did a little customization to get it to work very similarly (ie with the super key and the F1-F10 keys etc.). The only problem is that I can either get F1 and nothing else to work or F2-F10 and not F1 to work. Since F1 is normally just a help file, I chose to get everything but F1 to work with XFCE. I've attached my TWO keymap files (akita.xmodmap.new, which I have akita.xmodmap symlinked to, and userdefined.xmodmap, which I needed to get the F2-F10 keys working. I couldn't get them working with only akita.xmodmap for some reason -- it appears the keymapping in pdaXrom is a little screwy. If I only used akita.xmodmap, I could either get F1-F10 upon every press of just the number key or no F1-F10 at all -- ie I could only use F1-F10 if I never wanted to type any numbers. Maybe I'm incompetent, who knows.). Feel free to create a blend of Meanie's keymap files and these, or alternatively you could name these akita.xmodmap.xfce and userdefined.xmodmap.xfce and only load them in xinitrc.xfce (this may be your best option). You can just change every instance of akita.xmodmap and userdefined.xmodmap in my xinitrc.xfce file from my previous post to xmodmap.xfce and userdefined.xmodmap.xfce.
I've noticed that XFCE interprets Alt+4 as Alt+F4 (and likewise for all other Function keys), meaning I don't have to press Alt+Fn+4 (this may be a disadvantage if you actually need to type Alt+a number, but I don't think I've ever needed to do that).
With XFCE, the brightness/zoom key functionality must be added in manually. To do that, open the menu (ie right-click on the desktop or click the "Start"-like button), go to Settings, and select Window Manager Settings. Click on the Keyboard tab. Move the window up a little by holding Alt and dragging up (to allow you to see the bottom). You want to add some Command shortcuts. Double-click on an available menu item (or click it once and press enter). A dialog box will pop up. For decreasing the zoom, type in the command "xrandr -s 0". Then press OK. Another box will pop up. Press the Super key plus 1.
Repeat for zooming in, decreasing the brightness and increasing the brightness (All commands are outlined below):
Zoom in: "xrandr -s 0" -- Super + 1
Zoom out: "xrandr -s 1" -- Super + 2
Decrease brightness: "/sbin/setfl -" -- Super + 3
Increase brightness: "/sbin/setfl +" -- Super + 4
Could you include your other manager launch files? I'd like to do it manually by invoking a script, like I do for xfce4, but how to do that isn't immediately apparent from the scripts I've seen. (shrug)
Sure, I've attached my starticewm and xinit.ice scripts (starticewm is in /usr/local/bin and xinit.ice is in my home directory). I would recommend playing around with it though -- I only use IceWM occasionally and so it is not perfect. In fact, the brightness/zoom keys don't even work. Meanie has done some great customizations (or so I've heard), and so his .xinitrc for IceWM might be a better solution (provided you can find it). You can still use the starticewm script I have attached for Meanie's .xinitrc file, you would just have to change "xinit.icewm" to the name of Meanie's .xinitrc file (or rename Meanie's file to ~/xinit.icewm).
NOTE: rename all files to get rid of the .txt extension. Also, I renamed my userdefined.xmodmap file to userdefined.xmodmap.new to prevent any original userdefined.xmodmap file from being overwritten.