There's some stuff at bunnings which i use a lot. I think it's called One Time , or something (I'm not home at the moment but can check later). It's pre-mixed and very fine making it great for small gaps and hairline cracks. Great for this sort of thing. I always have some in the cupboard. If you don't get any other advice, I'll give you the name tonight.
Other than that, there's lots of premixed stuff at Bunnings. Go for a wander around, it's a good excuse.![]()