Expanding Panel with CollapsiblePanelExtender

I've setup a Panel that contains 5 buttons.  The Panel is collapsed so you only see ButtonUserAdd, ButtonGroupAdd and ButtonExportPermissions.

Based on code behind the Panel expands with ButtonUndo and ButtonSave appearing, what I don't understand is why when these buttons are before ButtonExportPermissions they appear on one line and are formatted wrongly.  However if they are after ButtonExportPermissions they appear fine.  Is there something I can do to fix this?

<asp:Panel ID="panelTasksContent" runat="server" CssClass="collapsiblePanelContent"
                        Width="146px" Wrap="False"><div id="divCbInherit" runat="server" style="display: inline"><asp:CheckBox ID="cbInherit" runat="server" Text="Inherit from parent" AutoPostBack="True"
                                OnCheckedChanged="cbInherit_CheckedChanged" Enabled="false" ToolTip="Turn folder inheritance on or off. Allow permissions to flow through from a parent folder or not." /></div><div align="left"><asp:Button ID="ButtonUserAdd" Style="background-image: url('Images/User.gif'); background-color: Transparent;
                                cursor: hand; background-repeat: no-repeat; background-position: left; padding-left: 15px"
                                runat="server" Height="25px" BorderStyle="None" Text="Add Users" Width="100px"
                                OnClick="ButtonAdd_Click" ToolTip="Add Users to this folder and subfolders depending on inheritence." /></div><div><asp:Button ID="ButtonGroupAdd" Style="background-image: url('Images/groups.gif');
                                background-color: Transparent; cursor: hand; background-repeat: no-repeat; background-position: left;
                                padding-left: 15px" runat="server" Height="25px" BorderStyle="None" Text="Add Groups"
                                Width="110px" OnClick="ButtonGroupAdd_Click" ToolTip="Add Groups to this folder and subfolders depending on inheritence." /></div><div id="divButtonUndo" runat="server"><asp:Button ID="ButtonUndo" Style="background-image: url('Images/undo.gif'); background-color: Transparent;
                                cursor: hand; background-repeat: no-repeat; background-position: left; padding-left: 15px"
                                runat="server" Height="25px" BorderStyle="None" Text="Undo Changes" OnClientClick="UndoChanges()"
                                ToolTip="Undo Changes." /></div><div id="divButtonSave" runat="server"><asp:Button ID="ButtonSave" Style="background-image: url('Images/save.gif'); background-color: Transparent;
                                cursor: hand; background-repeat: no-repeat; background-position: left; padding-left: 15px"
                                runat="server" Height="25px" BorderStyle="None" Text="Save" OnClientClick="SaveChanges()"
                                ToolTip="Apply Permissions to bolded folder and subfolders.  Depending on Inheritance." /></div><div><asp:Button ID="ButtonExportPermissions" Style="background-image: url('Images/export.gif');
                                background-color: Transparent; cursor: hand; background-repeat: no-repeat; background-position: left;
                                padding-left: 15px" runat="server" Height="25px" BorderStyle="None" Text="Export Permissions"
                                Width="150px" OnClick="ButtonExportPerms_Click" ToolTip="Will save a Tab delimited file containing the current permissions on the highlighted folder and subfolders." /></div></asp:Panel></asp:Panel><ajax:CollapsiblePanelExtender ID="CollapsiblePanelExtender1" runat="server" TargetControlID="panelTasksContent"
                    ExpandControlID="panelTasksHeader" CollapseControlID="panelTasksHeader" Collapsed="True"
                    ImageControlID="expandcollapse_tasks" ExpandedImage="~/images/collapse.gif" CollapsedImage="~/images/expand.gif"
                    SuppressPostBack="True" ExpandDirection="Vertical" CollapsedSize="100" ExpandedSize="150"/>