No very easy way.
Make one class as following

**************************************************
*-- Class:        changesetting (f:\wda\myvcx.vcx)
*-- ParentClass:  custom
*-- BaseClass:    custom
*-- Time Stamp:   09/07/06 09:14:12 PM
*
DEFINE CLASS changesetting AS custom
	*-- Save Exclusive setting
	cexclusive = .F.
	*-- XML Metadata for customizable properties
	_memberdata = [<VFPData><memberdata name="cexclusive" type="property" display="cExclusive"/><memberdata name="getexclusive" type="property" display="GetExclusive"/></VFPData>]
	*-- SET EXCLUSIVE OFF BY DEFAULT
	getexclusive = .F.
	Name = "changesetting"

	PROCEDURE Destroy
		LOCAL lmacro
		lMacro = THIS.cExclusive
		SET EXCLUSIVE &lMacro
	ENDPROC

	PROCEDURE Init
		THIS.cExclusive = SET("EXCLUSIVE")
		IF this.GetExclusive
		   SET EXCLUSIVE ON
		ELSE
		   SET EXCLUSIVE OFF
		ENDIF
	ENDPROC


ENDDEFINE
*
*-- EndDefine: changesetting
**************************************************

after that insert this class in all your forms.
By default all this forms are with SET EXCLUSIVE OFF.
IF you want in form SET EXCLUSIVE ON set GetExclusive property to .t.


>any easy way to write set exculsive off in load method in each mothod.( i have more than 100 forms).