Configuring lightning (thunderbird extension)

I'm using thunderbird on Kubuntu 17.04, and it's running very well for mail. I just installed the lightning extension (package xul-ext-lightning) and restarted thunderbird. When I went to add the Zoho calendar, it prompted me for a password, I generated a new application password, which it did not accept. I tried my regular Zoho password anyway (which, as expected, it did not accept because I have two factor authentication turned on). What password should I use? Thanks.