I suspect this is mostly Comcast's fault as it seems to work fine when i run it through my wireless hotspot but does anyone have an idea as to what i can do to fix this? Is it something on my end or is it simply Comcast blocking my P2P? If it is Comcast, is there any way around it?

Think of metadata as Phase 1 to a download. There are optional tags for magnet: to pull the INFO dictionary but Tix does not support these (yet).
What it does support is webseeds, if there is a HTTP server which has your file you can add that under the Options for the Transfer under PEERS

Modern clients can usually send you "metadata" to start the transfer. BUT if the content you want is rare, you may want to stick with importing .TORRENT files for that which already has the metadata so you don't have to wait in Phase 1, and then wait for Phase 2 the data to actually download.
This has happened to me before.