Please help : BP checkins activated makes link text disappear in TwentyFifteen

Please help to solve a strange problem:
When I activate BPcheckins (latest version with WP 4.1.1 and BP 2.2.1, Theme – default Twenty Fifteen) the link texts in side-bar disappear – some remain and some disappear. Please see the picture – https://s4.postimg.org/efbu0oxkd/vanishing_links.png

Thanks for your help.

https://www.ads-software.com/plugins/bp-checkins/