Originally Posted by JMS 
Set the lens to "A". You'll need to set the FL to 100mm. Make sure you have the latest firmware on your K100D as well. Note that apertures will show up in the finder as they would with out the convertor- ie, instead of showing as f2.8-f45, it'll still show up as f1.4-f22.
Also note that some copies of the MFTC have an internal problem where they don't transmit "A" data. If that's the case, ask me for help, and I'll post instructions on ow to fix it. Or, you could send it to me, and I'll fix it for a small fee.
Interesting...
I have what I believe is the same TC. It seems to take decen pics, but I seem to have an issue with the metering, or better put, with the numbers reported for the metering. I understand that not all TCs will properly report the new f-number correctly but mine seems to be doing weird things. When using my DA* 16-50 my K10D with TC reports f/2.8, which is to be expected. When using the DA 18-55 kit lens, it reports f/4 throughout the entire zoom range (instead of going to f/3.5 at 18mm and forcing down to f/5.6 at 55mm). This is the same on my FA 28-90mm. My Tamron 24-135 f/3.5-5.6 reports f/4.5 throughout the entire zoom range, and the weirdest example yet comes from my Quantaray 70-300 f/4-5.6. This is the Sigma DL Super version (the specs were identical, and it even has a rear lens cap with the greek letter sigma on the inside. This lens reports back f/1.2 (?!?) at all focal lengths. This phenomenon not only occurs with my K10D but occured with my film bodies (ZX-50 and MZ-7) as well.
Anyone have any idea whats up? The TC has 6 pins both front and back with the 3rd pin from the left slightly more recessed in the front and protruding slightly more in the rear.