Hi Guys, Sorry for not keeping upto-date life does get in the way sometimes! 
The original breadboarded layout I have pulled apart as I was practising getting 2x TLC5940 daisy-chained, I did notice some weird behaviour out of the breadboard (flickering led's) so I suspect that it might not be upto scratch so that is definitely one avenue - I'm going to give the 'shrimped' (am I using the correct terminology) another go, but this time going to build it on strip-board / matrix board - in t-he meantime however I purchased a RBBB Arduino http://shop.moderndevice.com/products/rbbb-kit from ebay - and put it together, works perfectly BUT still the CP2102 module refuses to play ball, but programs perfectly using RX/RT/RESET BLAH BLAH jumpered from a chipless Uno.
Doc: Differences,
FTDI232 - is the one that's used on the Uno itself! Works!! (at least from the uno)
CP2102 - the one I have - very cheap! Works?? People say it does, I have faith!!
PL2303 - Pass! Never seen one.
There all USB > Serial Bridges - electronically they shouldn't make a jot of difference, i think the trade off is support/price/reliability..Given the choice again, i would go for the FTDI232! 
Matt