Yes, I have realised that in-between and edited my post in a sneaky way (before you posted your reply )
Probably I clicked "new reply" and went away for a while

It is supposed to be a jQuery selector that will get all element from that DOM that have the class "slidetarget"
so is it possible that the stylesheet is not yet associated with the cell when you call jquery? (hot stylesheet is applied after setColdToHotTime millis )

It seemed to me, that when my command is ADD, it contains the row that will be added, but when my command is UPDATE, it has the row with the old values (probably it is the way it should work, just took me time to find out ).
yes that's correct, the row with old values will be updated with new values after the onChangingValues

The docs of onChangingValues say to leave to domNode alone, so maybe it is not a good idea to modify it via jQuery
yes that statement was added to avoid to deal with clients removing pieces from an element. As long as you just move pieces around you should not have any problem (anyway, are you using build 1396.4 or 1413?)

BTW is there a mean of telling at the initial load of the client, that client has finished loading the records it is supposed to display?
there is a onEndOfSnapshot callback that's called after the initial snapshot of ADD commands, not sure if this is a good hook for your needs

i use onCurrentPagesChanged() and I check the number of pages available via getCurrentPages(), because I had no clue where else to put the goToPage() call.
note that onCurrentPagesChanged receives as parameter the number of pages. That said you can call the goToPage method anywhere; the onCurrentPagesChanged is intended to be used to maintain an UI coherent with the number of pages available, but if you find it useful to perform other actions that's not a problem.