Not problems with installation -- but mail would not send. Spend alot of time with my mail settings. When I clicked "send" the message was cleared, but the editor remained - no message sent.
Finally I tried on some other sites, and discovered that if with the FCK editor (I didn't have the latest version installed) it did not work, but when I changed the editor JCE, the mass mail worked as advertised. Then the editor cleared away and a short "mail sent" message appeared afer clicking "send". Once the editor was changed, the mail setting did not seem to matter -- it worked fine for phpmail, sendmail and smtp mail. I did get an error message too, when the mail setting were incorrect.