modify wordpress plugin

I need modification of the worpress plugin: “We Advertise it” get plugin here: [login to view URL] Will like the following modification 1. Need to 2 new sets of predefined positions a. top left and top right position b. 3 mid content positions i. ad blocks should appear mid content after the first full stop given a defined amount of character(letter) counts in the post. ii. if letter count is defined as 100. you show the ad block after the first full-stop(.) after first 100 characters. iii. see image 2 of attachment c. See image 1 for front end illustration. Image 2 for plugin setting in wp-admin illustration d. NOTE: the plugin does not use snippets in post content and works irrespective of the Wordpress themes used. (don’t need to add codes to theme if I get a new theme) and it should remain this way. Please let me know if you have any commend, question or suggestion.