Warm start issue (Cold start no problem) - had to turn over approx 10-15 secs before starting when engine was warm after standing for a period approx 20 mins. When I first bought the car I don't recall having this problem.
Initially checked the 'blue' temp sensor signal was OK and reaching to the ECU - no issues here. I was putting regular 95 octane in the car. All other fuels here are Gasohol mix from 10 - 85 % and I avoid this for older vehicles rubbers fuel hoses etc. Working through the 'what has changed' scenario I figured the previous owner probably used 91 gasahol as a cheaper fuel. Returning to this fuel fixed the warm start problem. This agrees with what I read on one other forum from the US. There are other suggestions such as fuel pressure (don't understand why this is a problem only when engine is warm?). The engine seeems to run smoother with the 91 Gasahol.
Second issue was unsteady tick over, 'hunting' from 700 - 1500 RPM. This was fixed by replacing the Motronic 1.3 ECU. Note the ECU I removed had the same part number 0260 200 157 as the replacement (which I shipped from UK) though it was made in Spain not Germany. I have not seen a 'Made in Spain' replacement on Ebay / Forums etc.
I used a local mechanic for some items. Replacements parts were predominantly perished rubber such as all belts (including timing), engine mounts, front control arm rear mount, protective boots, rear suspension top rubber. We fitted a rear roll bar though this is not an original part on the 318i.
I also replaced the stereo with an original blaupunkt melbourne_sqr-39 tape unit. You can use a Sony Car Stereo Cassette Adaptor to plug into your phone and the sound quality is really good. Also get your calls over the speakers. I bought some 80's cassette tapes to complete the experience!
Pleasantly surprised with the result
Thanks to all those owners who have posted their experiences and helped me with this project.
Oneton in Thailand