All-in-one-event-calendar + Atahualpa V3.7.15 - Widget drop-down issue

Got an issue with the Agenda Widget in the All-in-one-event-calendar plugin, since V2.0.10 of Ai1ec.

The changed some of the buttons to a drop-down arrangement, which works fine with the TwentyThirteen/TwentyFourteen themes, but not with Atahualpa.

Basically the button on the widget always stays activated, so the (hidden) options are always visible.

I've tracked it down to:

Using a Browser plugin (WebDeveloper) I've found that completely removing from the above completely solves the issue.

I found that this is 'sort of' settable in Dashboard->Appearance->Atahualpa Theme Options under the tab Widget Styles section under Widget Content Box. I say sort of, as I can't remove the default CSS that's in that, I can only add additional CSS to it. No matter what 'display:' value I use, it never works, and I can't change those two values in the settings anywhere I look.

Any ideas where I should be looking? Is there a way to completely clear that from the CSS output, or do I need to resort to editing the code?

Note: I'm using a child theme of Atahualpa to simply add some site-specific images, so I can do any overrides in that to solve the issue, if necessary.

PS: If I set then it appears to work, however a bfa widget area I've defined (in the header) breaks and doesn't display.

PPS: I have a test site that exhibits the issue, but since it's on my home DSL connection I'd rather not post it in public (last time I did, I got indexed by so many bots I was with sub-par internet for a month, even after shutting down the port on my router).

BTW: Related post(s) on the Ai1ec forum: https://time.ly/forums/topic/subscri...lways-pressed/