Create InstType with dynamic section list

I need to select an installation type from a combo, each installation containing a specific required section (the user can not unselect it).
I tried the following but it is not working:

InstType "type1"
InstType "type2"
InstType /NOCUSTOM

Section "Section1" Section1
Section 1 RO
SectionEnd

Section "Section2" Section2
Section 2 RO
SectionEnd

...

Function .onSelChange
GetCurInstType $0
${If} $0 = 0
SectionSetText ${Section2} ""
SectionSetText ${Section1} "Section1"
${Else}
SectionSetText ${Section1} ""
SectionSetText ${Section2} "Section2"
${EndIf}
FunctionEnd
...

I also have the same thing within onInit.
My problem is that when selecting Type1 it is working fine, but when selecting type2 I only have an unselected empty section.

Any idea?

Changing the section names in .onSelChange doesn't show or hide them. That only works before the components page actually shows. You can create a fake section that'll only have a name, either "Section1" or "Section2", depending on the installation type.