Hey John,
Thanks for getting in touch and great question! I’m not entirely familiar with that plugin (I am assuming you are referring to the iThemes Exchange plugin) to be honest and am unsure as to how it would play with Beaver Builder depending on their combined use. How would you want them to work together? In that, I mean, would you want Beaver Builder to be able to modify iThemes elements or would you just want to be able to use both on given pages simultaneously? It appears the plugin is free so I may do some testing on my own this weekend, but feel free as well and let me know what you find. Of course, if there were to be issues, we would certainly look into them. 
Best,
Billy