I've now tried this base. First impressions of the base itself were very favourable, nice depth of flavour and sweet! Actually, given the ingredients, I can't believe just how sweet it turns out. It could be that your not using tinned toms has some merit in that respect CA.
For me it is a bit too tomatoey, edging perilously close to SnS's base in that respect. I think that would be the only thing I'd change in this base though, preferring a base that has no substantial overriding flavour and, therefore, allowing more tweaking at the curry cooking stage.
Made a CTM and well, meh!, difficult to praise or criticise in this because the base is masked by all the other trappings of a CTM. Tasted fine though.
Then made a Garlic Chicken chilli masala. Delightful it was! Still not as I remember BIR old stylee, but getting there, and very similar to using my current favourite base, that being Bruce edward's. Low spicing at the curry cooking stage is essential now I feel for the old style BIR taste.
I'd have to do a side by side now between CA's and Bruce Edward's to decide which I really prefer, but I think there's be hardly anything in it.
Good effort.