Ok.
Without a pause I thought the way to solve the above issue: I worked hard and finally I found a way.
Hidden function too was added to the shell to view system uptime when the mouse hovers over the time.
The following is the way to get full compatibility in Austerity Shell under any Vista Regional Format.
Enjoy!
If,"%pScrollBox1%",Equal,"Austerity",Run,"%ScriptFile%",Format
[Format]
TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","[time('h:nn')] [lowerCase(time('am/pm'))]","[time('i:nn')]"
TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc",";TimeLblOnMouseEnter","TimeLblOnMouseEnter"
TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc",";TimeLblOnMouseLeave","TimeLblOnMouseLeave"
RegRead,"HKCU","Control Panel\International","sTimeFormat","%Time%"
If,"%Time%",Equal,"h:mm:ss tt",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","[time('i:nn')]","[time('h:nn')] [lowerCase(time('am/pm'))]"
If,"%Time%",Equal,"hh:mm:ss tt",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","[time('i:nn')]","[time('h:nn')] [lowerCase(time('am/pm'))]"
RegRead,"HKCU","Control Panel\International","sShortDate","%Date%"
If,"%Date%",Equal,"d/M/yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d/m/yyyy"
If,"%Date%",Equal,"d.M.yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d.m.yyyy"
If,"%Date%",Equal,"d-M-yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d-m-yyyy"
If,"%Date%",Equal,"d/MM/yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d/mm/yyyy"
If,"%Date%",Equal,"d.MM.yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d.mm.yyyy"
If,"%Date%",Equal,"d. M. yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","d. m. yyyy"
If,"%Date%",Equal,"dd/MM/yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd/mm/yyyy"
If,"%Date%",Equal,"dd-MM-yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd-mm-yyyy"
If,"%Date%",Equal,"dd.MM.yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd.mm.yyyy"
If,"%Date%",Equal,"dd/MM/yy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd/mm/yy"
If,"%Date%",Equal,"dd.MM.yy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd.mm.yy"
If,"%Date%",Equal,"dd-MM-yy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","dd-mm-yy"
If,"%Date%",Equal,"M/d/yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","m/d/yyyy"
If,"%Date%",Equal,"MM/dd/yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","mm/dd/yyyy"
If,"%Date%",Equal,"MM.dd.yyyy",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","mm.dd.yyyy"
If,"%Date%",Equal,"yy.MM.dd",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yy.mm.dd"
If,"%Date%",Equal,"yyyy/MM/dd",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yyyy/mm/dd"
If,"%Date%",Equal,"yyyy-MM-dd",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yyyy-mm-dd"
If,"%Date%",Equal,"yyyy.MM.dd",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yyyy.mm.dd"
If,"%Date%",Equal,"yyyy.MM.dd.",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yyyy.mm.dd."
If,"%Date%",Equal,"yyyy/M/d",TXTReplace,"%TargetDir%\Program#$sFiles\LiteStep\themes\austerity\config\system_time.rc","ddd. mmm. d","yyyy/m/d"