I have downloaded the 1.0.5 IDE to A Win7 laptop from:
Unzipped to C:\data\Arduino.
I was able to start the .exe file, however, it has a painfully slow lag when selcting top menu items (File, Edit, Sketch, Tools, Help). I was able to set the Arduino Duemilanwe w/ Atmega 328 on COM8. Is there anything I cand to to fix this? I Googled the problem and did not find anything, so hopefully I did not miss this in reading the FAQ.
Update: I think that I was able to update upload the 'blink' routine: the red TX and RX LEDs blinked and now the green LED above it 'L' is red. The target board is a Seeeduino: Seeed Studio Bazaar, The IoT Hardware enabler.