I know many people have been looking for their own custom level signs when they make maps for portal and since they are originally models themselves, most have to stick with what is already available.
So what I've done is decompiled the model and then fixed it up in XSI a bit so that all the options there are for the sign is available, you just have to delete the stuff you don't want and then export the reference.smd & idle.smd; then using the provided .qc file - which I've reconstructed to match the skin settings of the original - you can have the same flickering animation the original portal levels have when each starts.
Now I'm afraid I'll only be providing this for XSI as I don't even have the other common modelling programs installed.
Open and Re-Save as a new file for EACH SIGN! - Makes it easier. You'll notice when you open the file that things don't look right - texture wise - and that normal so don't worry about that, they will still use the portal textures when you compile them.
Now the naming scheme I've used for the options are as follows:
Icon##('Off' or 'On') - 'Off' are the grey icons and 'On' are the solid black icons.
Level# - Starting Number, only 0 & 1 available right now.
Level__# - Ending Number, 0-9 Available.
Progress_## - Progress Bar, 0-19, one for each level.
Simply select the ones you DON'T need and hit delete.
HINT You can skin the awe_total.vtf to change the overall number of levels, ie '/19' change to '/5' if you wanted.
You will need to export both a "referance.smd" and a "idle.smd" for each new sign you make otherwise you'll notice parts of the model rotated 90 degrees.
Don't forget to edit the .qc file to change the $modelname value to a new one,
then for next compile:
the rest of the .qc file you won't have to edit unless you want to use different materials than the default ones or change the folder path they are located in.
When you compile the model you'll see some messages like this: 'WARNING: Model has 2-dimensional geometry (less than 0.500 inches thick on any axis)!!!'
You can safely ignore these as it just a warning about the flat geometry but that's just how the sign is made. Its just a warning that you have flat geometry, its not an error so your model will be fine.
If there are any problems with the file let me know ASAP so I can fix it. Otherwise enjoy,