I actually altered the Dell flash utility through hex editing to write my personal copy of the CT4390 config EEPROM last night since I own three AWE64 Gold cards (2x 4390 and 1x 4540), but I have no real way to test its flash capabilities other than the fact I didn't break the program. Never uploaded it anywhere yet due to that fact. I did upload the EEPROM contents to my site, however. And as mentioned, the other way is to use a programmer to write a known good copy of the data to the EEPROM (after removing the chip, of course). If only I could locate the SB2AWE program...
The CT3670 EEPROM dump I have is too large to fit in the Dell utility normally due to the IDE1 part of its EEPROM data, exceeding the usual 356 bytes (I ended up breaking the program trying anyway; danged pointers). Probably the same with the CT3990. Otherwise it's basically the same as the CT4502/CT4520 data.
And I actually previously owned such a CT3990 card, but I sold it about 3 years ago. I mainly got it because it had a Yamaha DB50XG daughter card attached to it. So, no personal EEPROM dump from me...
In general, the EEPROM contents in the utility are not encrypted, so any Creative AWE PnP card config that is 356 bytes long can fit easily without altering anything else.
Edit: to answer Jager's question, the config EEPROM contents in the Dell utility starts at offset 6436 and ends at offset 6599. If the utility (somehow) can be properly expanded to fit the entire 512 bytes, then the CT3670 and CT3990 config data can fit there at least.
Site update: cwcyrix.duckdns.org -> cwcyrix.nsupdate.info due to the former no longer working.