No, thats not the case, I have used for only one time,
I think there is another problem,
I have not imported any extension for using clock,
Is it the problem?
Yes. Add a clock component to the project and the problem will be fixed. The clock is not an extension, it is a built-in component. It is in the sensor group.
The tab action I saw was purely due to my emulator, not to my blocks.
For test, I switched my text entry box order in my global list to force a zigzag tab order upon the tab list. However, the tab action advanced the focus in row and column order in my test.
The Sourceforge download works OK for me. If the download does not start, click on the Problems downloading button, this should give you a link, or restart the download.