Hola!
Cada tema debes saber que es un archivo comprimido, bueno dentro de este tema hay un archivo llamado theme.xml, este archivo muestra la informacion del tema y de cada imagen donde sera ubicada ok, debes modificar este archivo, por ejemplo:
<?xml version="1.0"?>
<!-- Created with Sony Ericsson Themes Creator -->
<Sony_Ericsson_theme version="4.5">
<Author_firstname value="Remade by ~EdeBoi"/>
<Author_organisation value="SE-NSE | SEworld"/>
<Author_email value="x-edeboi-x@hotmail.com"/>
<Background Color="0x000000"/>
<Background_image Source="navigationBG+-AF8-SEMC+-AF8-Filtered.png"/>
<Calendar_weekview_markings Color="0x005384"/>
<Desktop Color="0x000000"/>
<Desktop_title_text Color="0xcfdae0"/>
<Highlight_text Color="0xffffff"/>
<Highlight Color="0x0fa5ff"/>
<Highlight_image Source="tabsHighlight+-AF8-SEMC+-AF8-Filtered.png"/>
<Highlight_small_image Source="everchangingBlueHighlight+-AF8-SEMC+-AF8-Filtered.png"/>
<Home_screen_text Color="0xcfdae0"/>
<Home_screen Color="0x000000"/>
<Home_screen_frame Color="0x000000"/>
<Home_screen_highlight_text Color="0xffffff"/>
<Home_screen_highlight Color="0x0fa5ff"/>
<Home_screen_highlight_image Source="activityMenuHighlight+-AF8-SEMC+-AF8-Filtered+ACA-Kopie.png"/>
<Home_screen_highlight_small_image Source="morelistHighlight.png"/>
<Home_screen_image Source="activityMenu+-AF8-SEMC+-AF8-Filtered.png"/>
<Home_screen_scrollbar_background Color="0x0fa5ff"/>
<Home_screen_scrollbar_slider Color="0xffffff"/>
<Home_screen_tab_text Color="0xffffff"/>
<Home_screen_tab Color="0x000000"/>
<Home_screen_tab_image Source="activityMenuTab.png"/>
<Home_screen_tab_unselected Color="0xcccccc"/>
<Home_screen_tab_selected Color="0x000000"/>
<Home_screen_tab_selected_image Source="tabsTabSelected+-AF8-SEMC+-AF8-Filteredac.png"/>
<Home_screen_tab_unselected_image Source="tabsTabUnselected+-AF8-SEMC+-AF8-Filteredac.png"/>
<Input_text Color="0xcfdae0"/>
<Input_image Source="popupPopup2+-AF8-SEMC+-AF8-Filtered.png"/>
<Input_marked_text Color="0x005384"/>
<Input_popup_text Color="0x005384"/>
<Input_popup Color="0xffffff"/>
<Input_popup_frame Color="0xcfdae0"/>
<Input_popup_highlight_text Color="0x005384"/>
<Input_popup_highlight Color="0xcfdae0"/>
<Input_popup_scrollbar_background Color="0x0fa5ff"/>
<Input_popup_scrollbar_slider Color="0xffffff"/>
<Input_small_image Source="input2-2+-AF8-SEMC+-AF8-Filtered.png"/>
<Morelist_text Color="0xcfdae0"/>
<Morelist Color="0x000000"/>
<Morelist_frame Color="0xb0e1ff"/>
<Morelist_highlight_text Color="0xffffff"/>
<Morelist_highlight Color="0x0fa5ff"/>
<Morelist_highlight_image Source="morelistHighlight+-AF8-SEMC+-AF8-Filtered.png"/>
<Morelist_scrollbar_background Color="0x0fa5ff"/>
<Morelist_scrollbar_slider Color="0xffffff"/>
<Popup Color="0x000000"/>
<Popup_dim Color="0x000000"/>
<Popup_frame Color="0x000000"/>
<Popup_highlight_text Color="0xffffff"/>
<Popup_highlight Color="0x0fa5ff"/>
<Popup_highlight_image Source="morelistHighlight.png"/>
<Popup_image Source="popupPopup2+-AF8-SEMC+-AF8-Filtered.png"/>
<Popup_scrollbar_background Color="0x0fa5ff"/>
<Popup_scrollbar_slider Color="0xffffff"/>
<Popup_text Color="0xcfdae0"/>
<Popup_title_text Color="0xffffff"/>
<Progress_bar_outline Color="0x005384"/>
<Progress_bar_fill Color="0xffffff"/>
<Progress_bar_slider Color="0x0fa5ff"/>
<Scrollbar_background Color="0xb0e1ff"/>
<Scrollbar_slider Color="0xffffff"/>
<Softkey_left_pressed_image Source="softkeyLeftPressed+-AF8-SEMC+-AF8-Filtered.png"/>
<Softkey_right_pressed_image Source="softkeyRightPressed+-AF8-SEMC+-AF8-Filtered.png"/>
<Softkey_text_left Color="0xb0e1ff"/>
<Softkey_text_right Color="0xb0e1ff"/>
<Softkey_text_left_pressed Color="0xe6f5ff"/>
<Softkey_text_right_pressed Color="0xe6f5ff"/>
<Standby_image Source="Aerial+AF8-f2nal.swf"/>
<Standby_operatorname_text Color="0xb0e1ff"/>
<Standby_operatorname_outline Color="0x000000"/>
<Standby_time Color="0xb0e1ff"/>
<Standby_time_outline Color="0x000000"/>
<Statusbar_clock Color="0xffffff"/>
<Tab_text Color="0xffffff"/>
<Tab Color="0x000000"/>
<Tab_image Source="tabsTab+-AF8-SEMC+-AF8-Filtered.png"/>
<Tab_unselected Color="0x999999"/>
<Tab_selected Color="0x000000"/>
<Tab_selected_image Source="tabsTabSelected+-AF8-SEMC+-AF8-Filtered.png"/>
<Tab_unselected_image Source="tabsTabUnselected+-AF8-SEMC+-AF8-Filtered.png"/>
<Text Color="0xcfdae0"/>
<Title_text Color="0xffffff"/>
<Volume_staples Color="0x005384"/>
<Wapbrowser_underline Color="0x005384"/>
<Wapbrowser_tableborder Color="0x999999"/>
<Illumination Color="0x003264"/>
<Desktop_style Type="File" Source="Aerial_desktop.swf"/>
<Desktop_style Type="File" Source="Aerial_desktop.swf"/>
<Softkey_middle_pressed_image Source="softkeyCenterPressed_SEMC_Filtered.png"/>
<Softkey_text_middle Color="0xb0e1ff"/>
<Softkey_text_middle_pressed Color="0xe6f5ff"/>
<Media_background Color="0x000000"/>
<Media_background_search Color="0xCFDAE0"/>
<Media_icon Color="0xCFDAE0"/>
<Media_text Color="0xacbfca"/>
<Media_text_background Color="0x000000"/>
<Media_highlight_icon Color="0xB0E1FF"/>
<Media_highlight_text Color="0xB0E1FF"/>
<Media_highlight_text_background Color="0x000000"/>
<Media_multiletter_search Color="0x000000"/>
<Media_history_bar Color="0x040404"/>
<Media_line Color="0xB0E1FF"/>
<Media_walkman_icon Color="0xffffff"/>
<Media_walkman_highlight Color="0xffffff"/>
<Media_progressbar_background Color="0xffffff"/>
<Media_progressbar Color="0x72b2da"/>
<Media_progressbar_buffer Color="0xCFDAE0"/>
<Media_wheel_icon Color="0xB0E1FF"/>
<Media_walkman_mode_icon Color="0x505050"/>
</Sony_Ericsson_theme>
Mira las frases con negrita, son las imagenes que el tema debe mostrar en el menu. Si quieres por ejemplo modificar el menu flash deberas modificar esta linea:
<Desktop_style Type="File" Source="Aerial_desktop.swf"/>
<Desktop_style Type="File" Source="Aerial_desktop.swf"/>
y poner el menu que quieras ok
Espero que haya quedado claro.
Un saludo!