Fixings for new bathroom - Tile Advice

[garfield59]

Hi all.
I have been asked to fit a bit bathroom cabinet in a friend's bathroom. The flat is one of many created from an ex call centre office and I'm told the walls are plasterboard on metal frame.
The bathroom is finished with slate grey tiles that are very hard. Masonry drill and spade tip tile drill barely mark it. I need to make 6 holes to hang the cabinet (typical IKEA) so I'm thinking of getting a 6mm diamond bit which should accommodate a reasonable size plug and screw fixing.
A sweep with a stud detector suggests that there is a metal upright behind at least one hole position (sods law).
The cabinet weighs about 10kg with its mirror door fitted and so I want to use some kind of plasterboard plugs but can I have the plug partly in the tile or do I push it through onto just the plasterboard? I don't think the tile will crack when I tighten the screw in the plug but each pair of holes for the top hangers are only 32mm apart.
If one hole does line up with a metal upright I'm thinking of using a plasterboard screw, through a plug in the plasterboard, straight into the upright.
Does all this sound reasonable? Any suggestions/comments welcome please!
Gary

 

[Time's Ran Out]

No use toggle type wall fixings

 

[garfield59]

No use toggle type wall fixings
View attachment 86175

Thanks for the quick response Timeless.
I do have some of those spring toggle fixings but the hangers provided by Ikea have slots that are too small to put anything larger than a size 6 or 8 screw through them.
However, I could use the toggle fixings to put a couple of level battens on the wall behind the cabinet and then screw the stupid Ikea hangers to the wood battens. This would also reduce the number of holes in the tiles from six to four and I could put the batten fixings away from the metal studs. Sounds like a plan.
Regards, Gary