Error when disable Buddypress "User Groups" and "Activity Streams"

Thank you for your useful plugin.

I catch this error:

Notice: Trying to get property of non-object in my-wp-root/wp-content/plugins/breadcrumbs-everywhere/includes/crumbs-core.php on line 36
Notice: Trying to get property of non-object in my-wp-root/wp-content/plugins/breadcrumbs-everywhere/includes/crumbs-core.php on line 37
Notice: Trying to get property of non-object in my-wp-root/wp-content/plugins/breadcrumbs-everywhere/includes/crumbs-core.php on line 38

My environment is

• WordPress3.8
• BubbyPress1.9.1
• Breadcrumbs Everywhere1.6

I disable “User Groups” and “Activity Streams” of Buddypress.
I think global variable $bp has no “groups” and “activity” property in this case.
So, line 36-37 in crumbs-core.php cause error.

I tried to fix them. This code work fine, no error has shown.
But I don’t know if this is the best way.

$page2 = isset( $bp->groups->root_slug ) ? $bp->groups->root_slug : "";
	$page3 = isset( $bp->activity->root_slug ) ? $bp->activity->root_slug : "";
	$page4 = isset( $bp->forums->root_slug ) ? $bp->forums->root_slug : "";

I would appreciate it if you would consider this.

https://www.ads-software.com/plugins/breadcrumbs-everywhere/