IKImageBrowser

I’m using Christian’s MBS IKImageBrowser to display images in a CocoaControl (MacOS 10.14.4). Since upgrading to Xojo 2018.4, when first displaying the window containing the control, the images are not drawn, but instead I only see the standard grey background of the control. Only when scrolling or changing the zoom factors are the images drawn. This effect only occurs when the number of images surpasses a certain number of items (in the vicinity of 500). When the number of images falls below this threshold, everything works as expected. Up until Xojo 2018.3, everything worked fine, even with thousands of images to be drawn.

Any ideas on how to fix this problem?
Thanks, Guido