CheckSynchronize(): is it needed?

[MementoMojito]

Hi,

I have just discovered CheckSynchronized() and I was wondering when to use it.
My current project (with a GUI) uses a lot the Synchronize() method from four different threads and I have never used CheckSynchronize() from my main thread but is it advised to call it?
I am recently experiencing some issues where my Gui would just become totally unresponsive and locked and I can't find where is it happening. My CPU is totally fine and I have tried to debug it but I just can't find where it is stuck.
I need to do some more testing but I wouldn't be surprised if it was some deadlocks due to Synchronize(),  could CheckSynchronize() be a solution?

Also a totally different question but is it safe to create a thread from a thread? Such threads are not assigned to any variable but I was wondering if it could potentially be a problem.

Any help or insights would be really appreciated.

Many thanks.