I have invested here but it is not my area of competence, so...

I have invested here but it is not my area of competence, so looking for any knowledge from others. Better to invest in areas you are competent in.

What is your price target once the MRE is announced? Don't expect major changes.
How have other exploration companies performed once MRE have been announced? In my opinion no, MRE already factored into the share price.
Is it dependent of general market conditions, which are not favouring risky assets like SNG? Why do you think SNG is a risky asset? And what do you mean by risk? As far as i can tell there is gold, so I do not think there is risk that a large proportion of the gold reserves will become resource.

At what point do institutional investors start controlling the share price? Institutional investors do not control share prices.

It is unclear what you mean by 'institutional investors' but I think you mean superannuation funds,etc. In general these would avoid SNG as it is too small for them to look at. (they are more interested in > $1B market capitilisation) Gold funds may be interested - but I can't see any on the register.

I think you should be more interested in 'sophisticated investors' rather than institutional investors. 'Sophisticated investors' are like 'Shark Tank'. They hover until the company needs money to say do more exploration, build a plant, commence mining. They then buy substantial shares at discount. But in return the Company grows.

My general opinion about investing is "I don't care about other investors" as it is too hard to predict. Instead I ask "does the Company have a 50% chance of being worth 10 times the value in 10 years?" If yes, I invest. So if institutional investors is really that important to you rather than the investment itself, I suspect there will be a large number of institutional investors in 10 years.