Thank you for the replies.
All e-mails I have received to date are from David. He did offer to send a replacement battery, but of lesser capacity than what I had purchased. He also offered to refund the cost of the battery, if this lesser replacement was not acceptable.
I then asked about the 48V10Ah, but it turns out that the throttle will then have to be changed. I also asked about the software, as it appears that I can't connect to the internal controller.
I went for a 36V system because it was the highest capacity battery on offer (576Wh or 36V16Ah) at the time and the replacement on offer (36V12Ah, or 432Wh, or 25% less energy) was not acceptable. I opted for the refund they offered, hoping to purchase a battery elsewhere.
Everything then went quiet - I heard nothing more from them and decided then to communicate via a PayPal dispute.
I received a reply from GM that my e-mail address must be faulty, as their replies to my e-mails were being bounced back - funny it happened all of a sudden...
Anyway, I asked for the refund (battery only, no shipping, no tax, no nothing apart from the battery) via PayPal and waited.
The days passed, but nothing happened until I escalated it to a claim.
Now everything is going down the toilet fast - PayPal advised that I must send the merchandise back - I presume they mean all and not just the battery (it is not clear) and then they will refund my purchase. But this is not what I want... As stated before, with this option, I shall the be out of pocket $600 with absolutely NOTHING to show.
I have since asked for a replacement battery, but still have receive no reply from GM.
This is a most unfortunate situation.
Gary, you do deserve the Super-G!! Thank you for your help. I was considering becoming a supplier in Ireland, as ebikes are now fast becoming more popular. However, I note your experiences on it and together with my own experience to date, I don't think that remains an option anymore.