OnStartup event is incorrect

Help & Support
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13

I don't need the script to run when Opus is not ready yet (when starting and restoring tabs).
A variable is created when Opus is ready and the other three events in the script run based on this variable.

Full script 
// Go to Previous Location
// (c) 2023 Ken

// This is a script for Directory Opus.
// See https://www.gpsoft.com.au/DScripts/redirect.asp?page=scripts for development information.



// Called by Directory Opus to initialize the script
function OnInit(initData)
{
	initData.name = "Go to Previous Location & Restore selection";
	initData.version = "v1.2.1(2023.10.20)";
	initData.copyright = "(c) 2023 Ken";
//	initData.url = "https://resource.dopus.com/c/buttons-scripts/16";
	initData.desc = "Jump to the previous location & Restore selection.";
	initData.default_enable = true;
	initData.min_version = "12.0";


}

// Called to add commands to Opus
function OnAddCommands(addCmdData)
{
	var cmd = addCmdData.AddCommand();
	cmd.name = "GotoPre";
	cmd.method = "OnGotoPre";
	cmd.desc = "";
	cmd.label = "GotoPre";
	cmd.template = "";
	cmd.hide = false;
	cmd.icon = "script";
}

// Called when Directory Opus starts up
function OnStartup(startupData)
{
	Script.Vars.Set("exec", 0);
}

// Called when a tab is activated
function OnActivateTab(activateTabData)
{
	if (!Script.Vars.Exists("exec")) return;
    var tab = activateTabData.oldtab;
	var Lister = tab.Lister;
    Lister.Vars.Set("preTab", tab);
	Lister.Vars.Set("prePath", tab.path);
	
	if (tab.all.count)
	    Lister.Vars.Set("preFocusItem", tab.GetFocusItem);
	else
	    Lister.Vars.Set("preFocusItem", false);
}

// Called before a new folder is read in a tab
function OnBeforeFolderChange(beforeFolderChange)
{
	if (!Script.Vars.Exists("exec")) return;
    var tab = beforeFolderChange.tab;
	var Lister = tab.Lister;
    Lister.Vars.Set("prePath", tab.path);
	Lister.Vars.Set("selected", tab.selected);
	if (tab.format && tab.all.count)
	    Lister.Vars.Set("preFocusItem", tab.GetFocusItem);
	else
	    Lister.Vars.Set("preFocusItem", false);
	
	if (Lister.Vars.Exists("preTab"))
	    Lister.Vars.Delete("preTab");
}

// Called after a new folder is read in a tab
function OnAfterFolderChange(afterFolderChangeData)
{
	if (!Script.Vars.Exists("exec")) return;
	var tab = afterFolderChangeData.tab;
	var sourcePath = tab.path + "";
	var Lister = tab.Lister;
	// Save subfolder selection
	var action = afterFolderChangeData.action;
    if (action != "forward" && action != "dblclk" && !Lister.Vars.Exists("bcbNav")) {   //if (action != "forward" && action != "dblclk" && action != "normal") {
		var subPath = Lister.Vars.Get("prePath") + "";
		if (action == "normal") {
			var match = subPath.replace(sourcePath, "");
			if (match == subPath) return
		}
		Lister.Vars.Set("subPath", subPath);
		var subSel = Lister.Vars.Get("selected");
		Lister.Vars.Set("subSel", subSel);
		var subFoc = Lister.Vars.Get("preFocusItem");
		Lister.Vars.Set("subFoc", subFoc);
		Lister.Vars.Set("bcbNav", "")
		if (action != "refresh") return
	}
	// Restore selection
	if (action != "parent") {
		if (Lister.Vars.Exists("subPath")) {
			var subPath = Lister.Vars.Get("subPath");
			if (sourcePath == subPath) {
			    var subSel = Lister.Vars.Get("subSel");
			    var subFoc = Lister.Vars.Get("subFoc");
				var cmd = DOpus.Create.Command;
				cmd.ClearFiles();
			    var focItemSel = 0, eItem;
	            if (subSel.count) {
					for (var e = new Enumerator(subSel); !e.atEnd(); e.moveNext())
					{
						eItem = e.item();
						cmd.AddFile(eItem);
						if (eItem + "" == subFoc) focItemSel = 1 
					}
	            }
			    if (cmd.filecount)
			        cmd.RunCommand('Select FROMSCRIPT');
			
			    if (subFoc) {
			        cmd.ClearFiles();
			        cmd.AddFile(subFoc);
			        cmd.RunCommand('Select FROMSCRIPT SETFOCUS');
				    if (!focItemSel)
				        cmd.RunCommand('Select NONE');
			    }
		    }
			Lister.Vars.Delete("bcbNav")
		}
	}
}

// Implement the GotoPre command
function OnGotoPre(scriptCmdData)
{
	var tab = scriptCmdData.func.sourcetab;
	var Lister = tab.Lister;
	var cmd = scriptCmdData.func.command;
	cmd.ClearFiles();
	
	if (!Lister.Vars.Exists("preTab")) {
	    if (Lister.Vars.Exists("prePath")) {
			var prePath = Lister.Vars.Get('prePath');
			var selected = Lister.Vars.Get("selected");
			var preFocusItem = Lister.Vars.Get("preFocusItem");
			cmd.RunCommand('Go "' + prePath + '"');
			var focItemSel = 0, eItem;
	        if (selected.count) {
		        //cmd.SetFiles(selected);
		        for (var e = new Enumerator(selected); !e.atEnd(); e.moveNext())
		        {
					eItem = e.item();
		            cmd.AddFile(eItem);
					if (eItem + "" == preFocusItem) focItemSel = 1 
		        }
	        }
			if (cmd.filecount)
			    cmd.RunCommand('Select FROMSCRIPT');
			
			if (preFocusItem) {
			    cmd.ClearFiles();
			    cmd.AddFile(preFocusItem);
			    cmd.RunCommand('Select FROMSCRIPT SETFOCUS');
				if (!focItemSel)
				    cmd.RunCommand('Select NONE');
			}
		}
		return
	}
	
	var preTab = Number(Lister.Vars.Get("preTab"));
	var tabs = tab.lister.tabs;
	for (var i = 0; i < tabs.count; i++)
	{
	    if (tabs(i) == preTab) {
            //cmd.RunCommand('Go TABSELECT=' + i);
			cmd.RunCommand("Go TABSELECT=$" + preTab);
			return
		}
	}
	cmd.RunCommand('Go TABUNDOCLOSE');
}