Cold weather Alt

[Barronflyer]

Hi there

I'm hoping someone can provide assistance on the following

I've been studying the cold weather alt tables. I understand how the correction to MSA is accomplished but I'm a little confused with correction to procedural altitudes (IAF,FAF, MDA etc). Should I be correcting the FMC altitudes only in this regard or am I required to set the MCP ALT to these adjusted altitudes. If so do I need to advise ATC each time I do this?

And if ATC clear me e.g. to ANY altitude am I required to set that altitude exactly with no correction?

Any info would be appreciated