Network traffic stops when Screen saver activates and corrupted downloads on LAN

Hello everybody (:WAV)
First of all let me congratulate on Your great firewall (L) It is great to have such good firewall for free! (:AGL)
I have just installed the latest version having uninstalled before the 3.0.13 version, and I noticed that it has configured all access to my home LAN and WAN perfectly, without needing to work on that stupid scvhost.exe … (:CLP)
Anyway 2 very nagging things remained ???
First when my Windows Vista screen saver starts (PhotoScreensaver) comodo seems to stop all network traffic, and my dialup connection fall after a little!! It is very nagging coz it takes so long to dial again and be connected! :-[
The second horrible problem is that very often when I download stuff from the PCs connected in my LAN or WAN, they r corrupted!! If I stop comodo, they download fine :frowning:
Some techical info on my system:
Pentium D dual core 3.2Ghz, 1GB DDR2 666MHz Dual channel, Asus NVidia 7600GT, USB SoftV92 data fax modem with SmartCP, Windows Vista Ultimate, Avira Antivir Classic Personal Edition.
the PC on LAN runs WinXP pro and presented the same problem with browsers Opera, Mozilla, an IE even disabling its firewall. Notebook on WAN run Vista ultimate (:KWL) Both problems do not happen without Comodo.
Thank You very much in advance
Stefano B.