I have to disagree; You may not be able to push a PCiii map into a PC-V using the PCiii software - I can not confirm that as I don't have the old software anymore.
However, You can open a PCIII map(*.djm format) in the PC-V software, convert it (save as) a PC-V format(*.pvm). I just did it on my netbook before responding. I did this with the custom (dyno) map from my '04 to play with it in the '09. The difference, IIRC, is that the PC-V has a 250 rpm increment on the tables, and I think the PCiii had 500 rpm increments. Some will jump in and call me out if that's incorrect.
Now, one option you can utilize with the PC-V to test maps back to back on the go is loading both of them and installing a simple open / closed switch. The instructions show you which terminals to plug the wire into, run it to a switch (mine's mounted up on the left panel behind the glovebox lid). You can switch on the go; if you've got a laptop plugged in, you can see the map change on the screen when you flip the switch. Load two maps, ride on one, switch to the other, ride some more. Keep the one you like better.
I run a zero map for highway, then a hybrid smoothness map for off the highway. Just flip the switch. I'd suggest starting with a canned table/ map first. Don't start manually changing numbers in the cells unless you've spent some time to know exaclty what your changing. I'd defer to Uselesspickles - he's spent the time with fuel tables playing with them to include the afr moty install on his '08. Maybe he'll wander by and enlighten us some more...
Hope this helps.