1.) You have to reinstall the DS profile exploit, you removed it (did you play a DS game or do a system format? those are common ways of removing it). Put the spider3DS tools files on the root of your SD and go to whatever webpage you originally used to install the exploit (look in whatever guide you used).
2.) For your failed to connect issue, are you using the right local IP for your 3DS? Check your router status page and look for your Nintendo 3DS, and if it has a different IP than "192.168.0.5" then edit your run.bat to be whatever IP it is listed on your router page. Also, you are booting the cfw by holding L when you press the DS profile button, correct? Because you need to hold L to boot it into the (buggy) mode that lets you install .cias over the network.
3.) Sometimes it takes me a few tries of using run.bat to successfully connect. It might be placebo, but putting my 3DS closer to the wireless router seems to make it work better.