Transferring US Shares to IG - some questions

[icarus33]

Hi to anyone reading this,

I'm new to this forum and hope these questions haven't already been answered. If they have please do close this post and redirect me.

 

Some years back I opened a Charles Schwab US account and transferred money over to the US to start trading. I have a few longer term US holdings and want to transfer into IG but trying to get my head around some tax related points and 'where' my money would physically be:

Currently the dividend payments in the Schwab account are instantly taxed 15% - Does the same tax apply to the same US stocks held in IG?
Are the share holding converted to share CFDs or actual shares? 
Is my money technically back in Australian shore?
And if I selling a holding, I assume I could then just withdraw/transfer that cash into my normal Australian bank account?

Hope these aren't silly questions!