Serious or not so serious!?

[GtiMaxi]

Recently iv noticed a smell from my exhaust, it's a burning oil smell and it is a lot thicker and stronger smelling if I have been sitting on idle for a bit.

The cars got a full decat, and remapped, 267bhp.

There isn't really a colour to the smoke to its hard to tell.. Any common faults I should know about?
Not sure if it's turbo related or something that's a pain in the rear like rings.

[GrayMK5GTI]

Is the oil level going down on the dipstick?

Hot engines can make a bit of a smell so it may be nothing. . .

[GtiMaxi]

It's always used oil a little since iv had it, used a little water but I put that to a little leak in the radiator