Preferences > Event Display > Colorize Track controls, move the slider to Max, hit Apply and OK. You'll then see the whole 'header' display the same colour as you previously saw at the small bit on the left.
Steinberg forum member since aug. 2002
Cubase 7.5.10 x64 with jBridge | WaveLab Elements 8 | Windows 7 x64 Dual Boot on 2 x 128GB Crucial m4 2.5-inch SSD + 2 x 256GB Crucial m4 2.5-inch SSDs for samples and project/audio files | P5E | Q6600 @ 3.24GHz | 8GB RAM | Echo Layla 3G PCI | ASUS HD6570 | Vox ToneLab SE | Mackie HR624 MKII | 2 x UAD2 Solo PCIe | 2 x 24" LED monitors...
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