Problem emailing iRp charts (MAC)

Hey all, I've got a slightly different problem - I'm using iReal Pro on my Mac laptop (I've been using iReal for years on my iPad, but I just downloaded the OS X version onto my Mac about 2 weeks ago), & my email (GMail) isn't appearing in the Share options. When I go to "More", I get these options, after choosing "Share Chord Chart":

Messages
Forums
Save to Disk
Print/PDF
MusicXML
More...

When I select "More", I get a Mac window titled "Extensions". Under the menu on that window, there"s a list of apps, w/ check boxes next to each one. GMail is listed there, & its' box is already checked, but grayed out - it won't let me select or unselect it. A couple of other apps are the same (Messages & AirDrop). BTW, I'm running El Capitan on my Power Mac.

So, I guess what I need to do is somehow "associate" GMail w/ iRealPro, but I can't figure out how to do that. I don't see anything in the System Preferences on my Mac for choosing a default email program, & there's nothing about this in Preferences in iReal either.

I have figured out a simple workaround - I just choose "Save to Disk", save the chord chart file to the computer, & then attach it in an email. But this seems like having to do a couple of extra steps (compared to emailing a chord chart from the iPad version of iReal), & was just wondering if this is the preferred method that the developers wanted for emailing chord charts in the OS X version of iReal or not?

Thx,

McJazzer