Likewise I've suffered a similar issue. But not with your particular example. I've found LW being very slow to bring up a stable option/pop-up window. It beach balls whilst I'm trying to click the option for yes/no or Apply/OK, etc. I've had this issue over several areas of LW when option/pop-up windows appear. I wondered whether it was semi related to me having such a large burdon on the program with a large incomplete folder & larger amount of shared files. LW for mac has long had an issue with Java & also memory. The most recent version is supposed to help overcome some of those issues. It certainly does use less ram than the 4.0 or 4.1 beta series used. But it's still an issue. And not just with popup windows.

As far as your problem with the re-trying to verify & complete the dwnld, LW is supposed to give up after a certain no. of attempts. I think it's 6 attempts.
May I suggest you update to LW 4.2.4