I assume it’s stalling on start-up and not stalling once it’s up and going. I would be checking the cold enrichment system, which seems fine in cold conditions, but not doing the job on warmer days.

YOU are caught in a difficult situation not of your making. Daewoo has announced it is pulling out of Australia and that will make it hard when it comes to resolving problems. In the meantime, Holden is saying its dealers are taking responsibility for service and problem resolution. I'm sure that it will still be difficult to resolve problems like yours. I would suggest you persist in getting a satisfactory answer to your concerns, first with your dealer, then with Holden if you aren't satisfied. Phone Holden's customer assistance number, which you'll find in the telephone directory.