Open Astro, navigate to the download folder, and it doesn't let you install?
Sorry, I don't know what steps you've done. Astro doesn't auto open a file after a download. You might be on the download screen and not within Astro at all right now.
downloaded using browser. shows in astro 236d1265663039-2-1launcher2-apk-now-2-0-1-2-1 app drawer-5-screens-launcher2-11b. tap on app and error message says could not be loaded---java.util.zipexception expected end of central directory signature. i think i've tried everything but