First and foremost..Don't beat yourself up too hard if bagseed doesn't germinate..It might not be viable..Second, I concur, make sure you use some decent soil..Additionally, I too use a zip lock to germinate...soak a piece of paper towel..squeeze the crap out of it till pretty much dry place seed in and seal up..put in dark place..for your temps, you're fine..I typically avoid putting on warm appliances..just my preference.I typically try to stay away from too much heat >80 as fungus can destroy them..again make sure paper towel is squeezed of excess water..it should not be dripping..Once sprouted, (2-5 days typically)plant tap root down 1/4 inch in soil...place light close to soil..you want heat from the light you are initially using as this is how the plant will know which direction to surface...led's should work, but put them closer to the soil...Be sure to watch for seed breaking through soil as LED can harm them if to close..GL..You'll be fine..If you're concerned still, sprout your new seeds one at a time..sprouting a new one each time you have success, so you don't wreck all your seeds ..just in case you are doing something wrong.
Good luck
Toad