Hi Rak,
I would use the small business community for RV042 issues.
Personally I would do the following after reading the following post, especially after a software upgrade;
https://www.myciscocommunity.com/thread/12384;jsessionid=35C509DCCC232DD58511DC3E8EDE47E8.node0
Do you have any stats to indicate if the wireless is the instigator of the RV042 loosing the VPN link ?
But anyway I would do the following;
step 1. reset to factory defaults after a software upgrade ( tough to do, but I would do it)
Step 2. Make sure you have, under advanced options in the VPN gateway to gateway section, keep alives selected on that VPN tunnel
If these two steps fail, and the wireless link is not the instigator of the VPN link going down, then I could call the SBSC at;
http://www.cisco.com/en/US/support/tsd_cisco_small_business_support_center_contacts.html
Hope this help,
And remember to try to use the small business part of this support community, you probably will get a faster response.
https://supportforums.cisco.com/community/netpro/small-business
regards Dave