Fast answer to a stupid question question:
If I want to apply a GE to a filter's cut off frequency I adjust the cut off frequency by adding to the original frequency an amount given by my adsr GE (ex. from 100Hz to 220Hz and back to 100Hz), whether I use a low pass, high pass or band pass filter?!,
or I add this amount for the low pass, subtract it for the high pass and whatever for the other filters?
And secondly, how much should be this amount given? 0~100Hz, 0~1000Hz, or it depends of the cut off frequency's price?

I not quite sure what you mean: But i think you just want to modulate the frequency of the filter with your envelope.

Second one first: The amount depends on the kind of effect you want to achive with this kind of filter sweep so the best would be to create a simple *~ object to adjust the amount of the envelope and then add it to the already set frequency of the filter.
This answers also the second question: If you use negative values with the *~ object the frequency will decrease, if you use positive values it will increase. So you can choose for each filter if it will decrease or increase the frequency. But i don't know what you want to achieve. So adjust it till it sounds right?

I hope i got your issue right.

Cheers