Restrictions in Datawindow Modify() or Direct Property Access Syntax?

Hi,

Are there any restrictions on  how complex could be an argument string in Datawindow Modify() function or in datawindow property access syntax?

I need to control Enabled property of a Datawindow field with complex statement using many IFs.

When I try to Modify() Enabled property using the following kind of expression (string)

if(1=1,1,0)=1 OR if 1=1,1,0)=1 OR if 1=1,1,0)=1 OR if (1=1,1,0)=1 OR if (1=1,1,0)=1 OR if (1=1,1,0)=1

I'm getting a (validation) error pointing to the last character of the submitted string.

It does not matter if it is done by dw.Modify() function or by property access syntax: i.e.  dw.object.field.enabled='expression'

However it is OK if I remove any one of the IF() components inside the expression string. I.e. if I have not 6 but only 5 IF conditions.  Also the same expression  is  always validated from inside datawindow painter.

So, there number of IFs in such expressions is limited to 5 (or 6? , it is saturday today, so I'm not sure was it 5 or 6, IFs really...)

Environment:  PB 12.5 Classic, Windows XP.

Thank you in advance