I don't see it listed there anymore.  What happened?

I recently updated CCC so I could mine with my Radeon HIS 4850 card.  I am about to replace it with a Sapphire 7850.  Do I need to uninstall CCC and re-install it or do I not need to update any software?

I have an older mother board (ASUS P5Q3 Deluxe) with PCI-E 2.0 slot and a 550W power supply.  I want to upgrade my GPU to a AMD 7850 850 MHZ or 920MHZ.  I'm pretty sure the mobo and PSU can handle the card but will my hash rate for LTC be slower than if I had a motherboard with PCI-E 3.0 slot?  Could it even handle a 7950?

Until last night I was able to connect to slush's pool using guiminer but now I get these errors:

2013-04-16 11:43:11: Listener for "BTC" started
2013-04-16 11:43:13: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:13, checking for stratum...
2013-04-16 11:43:13: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:13, started OpenCL miner on platform 0, device 0 (ATI RV770)
2013-04-16 11:43:13: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:13, no response to getwork, using as stratum
2013-04-16 11:43:13: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:13,  No JSON object could be decoded
2013-04-16 11:43:23: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:23, Failed to subscribe
2013-04-16 11:43:25: Listener for "BTC": api2.bitcoin.cz:8332 16/04/2013 11:43:25, IO errors - 1, tolerance 2

I didn't change any settings.    I have my maximum hash rate but no shares.  Can anyone suggest what's wrong?  Thanks.

I've just started mining bitcoins with guiminer on slush's pool.  I now want to try merged mining with namecoins.  I've installed namecoinj gui, configured the daemon, got a couple of namecoin addresses, and downloaded the blockchain.  I've entered my namecoin address on bitcoincz but no namecoins are being generated.  How do I start generating namecoins.  Do I have to register a namecoin domain?