Did you md5sum Lubuntu 12.04 after you downloaded the iso and put it on the cf card. Might be a corrupted iso download and install. This will cause strange behavior when running applications. Some will work, some won't. CF cards are slow at best. I used a ide to cf adapter and use a Hitachi 8 gig Microdrive
in the hardrive bay instead which is faster and more durable than cf. It won't work though without the ide to cf adapter. Because I tried with a pcmcia to cf adapter and bios wouldn't recognize it as a ide device. Looks like This
which goes in the hard drive caddy.
the 240z contains a either a 500 celeron or 600Mghz CPU with a resolution of 800x600 or 1024x768.
240Z CEL 500
P3 600 64(192) SDRAM 10.4" TFT 800x600
1024x768 NeoMagic MagicGraph 128XD (NM2160) 2M
Silicon Motion LynxEM+ (SM712) 2M ESS Solo 1 (ES1946)
Cirrus Logic CS4281 Lucent 56k V.90 Win
Maximum Memory: 192MB
I run Antix on my old IBM a22m 1000hz cpu 512MB ram and also IBM T23 1.2 ghz cpu with 1gig of ram. Not that I am recommending another distro. Just saying what I run OK on older machines. So I am not Lubuntu proficient.