Yes we are aware of the issue, have fixed the issue and have submitted the fixed version to Apple for "Review". Hopefully it will be available for you to download by the end of next week.
In the United States, on the leftmost column the week starts with Sunday. In some other countries, such as Germany, the leftmost column starts with Monday. The date it picks for "Today" is correct, what is wrong is the column headers. If you can just pretend that the leftmost column is Sunday until TM v5.1 comes out that would be great. Since Apple does not provide a calendar control, we wrote this from scratch for our users. It is probably the only calendar that also works in Landscape mode! Unfortunately we messed up and didn't realize that certain countries had a different layout (different starting day). We're so sorry for the trouble.
