I’ve been using Klok 1.5 RC 1.1 since the beginning of August and have had this problem happen but it is random in occurrence. One day’s worth of tasks are stacked on top of the each other when I close the app. When I start Klok the next day, the previous day’s tasks are suddenly cascaded. Making sure that there is at least a minute between tasks doesn’t fix this appearance.
Just thought I’d pass this along. Klok is a great app otherwise!