Question: I know that I can update my ECT record (using InfoPath forms I created for the external lists), by passing the BdcIdentity (ID) to the form and it will find that record and enable me to edit.

How do I edit a record without the BdcIdentity ID. Say I know some of the other IDs I need to uniquely identify a record. EG, MyID=1

How can I get the infopath form to retreive the record where column MyID=1?? so I can update.

thanks,
KS

Answer: 
Just for others who might come across this, try a full refresh by pressing CTRL+F5. This is likely a cache issue, especially if it only occurs in one browser. This happened to me after the Default Website was started while the Portal Web App was stopped and I hit the site. Once I stopped the Default Website and started the Portal Web App, I was still seeing the IIS Welcome screen. CTRL+F5 forced IE to reload the site.
Since the new version of IE, it cache all get requests. So that is possible that the site is already cached. Try to empty it and then it will be working.