When we set a conditional formatting suck like "B2:B200   value >2500", then if I edit more steps such like drag to fill some cells...etc, or others... 
then my conditional formatting will change to be something like this:
B2                                    >2500
B13:B16                               >2500
B64:B66;B59:B61                       >2500
...
...
...
...
...
...
...
...
...

more steps editted, more formatting will appear automatically, and finally the unconditional formatting editor appears in a big mess.
I thought although the uncdonditional formatting editor now is very dificult to see in order, but cells´ value in the workshee of calc are still correct. So I just let it be.

However disaster comes soon, one day I just find the worksheet goes very very very slowly and crashs till I can not use it any more. I think maybe it´s caused by the mess of unconditional formatting. So I start to organize hundreds of unconditional formattings that produced by calc automatically, now it´s only this one again in my unconditonal formatting editor like "B2:B200         value>2500", and this worksheet comes back to go fast again.

My libreoffice Version is 4.4.1.2. I hope this bug could be fixed as soon as possible. Best wishs!