water level ok
pan screwed to floor with a nut as a washer or what ever it's meant to be
isolation valve on toilet feed round the wrong way
soil stack ok.
i don't know why he use a flexi pan connector instead of a ridge one.
you sure it's from water and not connector behind.
Hard to say without looking at it personally but the flexi connector doesn't look a good fit to me so the smell could be coming from there. While you have no flooring down i would try and fit a rigid connector (they are not expensive) and move your pan accordantly if possible
thanks for the intrest and feed back, problem sorted with flush and smell, hole internal in toilet, water escaping when flushed not coming out of top of the bowl, 20% of it going stright to the soil and the stench is coming up that hole and coming out of the holes around the bowl at top but yes i understand what u say about the fitting it is s... so many poeple said as well i will sort that thanks !!!