SiteOrigin Testimonials from So Bundle

Hi

I am using Pinnacle Child theme.
1.I made a new page in it (add new):

test

2.I added new (1column) row in PB – works
3. I added SO-Testimonials widget into and published – works
4. I went into widget and wrote Title – “done” button – works
5. I “added new testimonial (+)” – “done” button, “X” button – all dead :(

I’ve found that during this on page appears as below:

Fatal error: Uncaught exception ‘Exception’ with message ‘parse error: failed at `@testimonial_background: ;` line: 202’ in /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/inc/lessc.inc.php:3460
Stack trace:
#0 /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/inc/lessc.inc.php(2273): lessc_parser->throwError()
#1 /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/inc/lessc.inc.php(1795): lessc_parser->parse(‘nn.so-widget-so…’)
#2 /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/siteorigin-widget.class.php(629): lessc->compile(‘nn.so-widget-so…’)
#3 /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/siteorigin-widget.class.php(502): SiteOrigin_Widget->get_instance_css(Array)
#4 /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widge in /domains/test12824.futurehost.pl/public_html/mediathor.eu2/wp-content/plugins/so-widgets-bundle/base/inc/lessc.inc.php on line 3460

Any idea about the reason?
Regards
PAtryk