Thank you for your coments.
Regarding initialization process we have already moved it to server side (as service as Youval adviced) and then moved backed to client side. Initialization on server side does not change anything on fast client PC. It propably will reduce time on old slow client PC's (wich to be honest we have not tested with server side initialization). Server side processing has one more disadvantage - once you have quite big load on server (let say 200 - 500 concurent clients) it will slow down a lot. That is why i prefer to leave it on client side.
There is one more idea we have to improve performance - but it sacrifices some flexibility - we can remove width and/or high as paremeters and set is inside initialization logic. It should recuse loading time 0,5 - 1 sec. on fast computers (we will know it for sure after our vacation - I mean after 25th of August).
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