Here's a quick little plugin I'm currently poking at for WordPress that I think many web-comic peeps will find handy. Requires both Comic Easel and s2member. This is getting close to a release state, however it is still beta.

SMEW-comic-easel-heart-s2member-v0.1.4

=== Comic Easel <3 s2member ===
Requires at least: WordPress 3.0, Comic Easel Plugin, s2member
Tested up to: WordPress 4, Comic Easel Plugin, s2member

s2member integration for Comic Easel for drip feeding of comic posts. Will let subscribers 'preview' comics for specified times before opening up to the wide world based on user roles. Will also allow different size images to be displayed based on user roles. Only works on Single Posts.

Known Issues: This plugin currently breaks Image Maps and Light Box use inside of Comic Easel. It is recommended you do not use this plugin until the next revision of both SMEW Comic Easel <3 s2member and Comic Easel if either of those two functions are necessary for your site.

Upcoming: Adding a backend setting UI to change things such as the custom post type slug name. Fix for the Image Map and Light Box issue coming with next revision of both SMEW Comic Easel <3 s2member and Comic Easel (will require both). Add descriptions to Settings page.

Update:

v 0.1.4 - Fixed the comic display so that it would correctly display/interact when 'Comic Easel'->'Clicking the comic goes to next comic' is active. Removed add_action via Frumph's wonderful suggestion. Changed timestamp creation to fall more inline with WordPress standards.

v 0.1.3 (internal release only) - Added the ability to set image size via membership level. Currently hard coded to the 4 basic membership levels that come standard with s2member. It can be wonky since it can be set in any random order, so use with caution.

v 0.1.2 - Fixed bug where variable was feeding into wrong function.

Wow- not even 48 hours old and I find my first bug! Basically, the name was causing WordPress to try and update the as if it was Comic Easel. Not helping. So I renamed the plugin slightly to include the studio's abbreviation, SMEW, at the front. The link above has been updated with the newest version. If you really want the older version, I have it listed below.

SMEW-comic-easel-heart-s2member-v0.1.2
SMEW-comic-easel-heart-s2member-v0.1.1
comic-easel-heart-s2member-v0.1