[XXXler]

R.i.m.s.k.y.

Код:

[Languages]
Name: russian; MessagesFile: compiler:Languages\Russian.isl; 
Name: english; MessagesFile: compiler:\Default.isl; 

[Components]
Name: a; Description: "{cm:abcd}"; Flags: disablenouninstallwarning

[CustomMessages]
english.abcd=abcdefg
russian.abcd=абвгд

...

WizardForm.ComponentsList.ItemEnabled [WizardForm.ComponentsList.Items.IndexOf (ExpandConstant ('{cm:abcd}'))] := False;