Thanks for using Lunascape! Sorry you're having problems with it.
When you click the engine name next to the address bar to switch engine, which engine name is displayed before the switch?
Could you provide us with a few explicit URLs for which the link disappears in the address bar, and for which "page cannot be opened" appears?
When you tried to submit your question to this forum, which engine was in use?
Also, which version of Lunascape are you using?